It’s been an epic process – most papers get published (or rejected) in less than a tenth of that time. The paper is accompanied by an unusual Editor Comment (p. 1054) stating that in the paper we have presented a view on atmospheric dynamics that is both “completely new” and “highly controversial”. They accept that we have made a case to be answered: they clarify that “the handling editor (and the executive committee) are not convinced that the new view presented in the controversial paper is wrong.” That’s not exactly an endorsement but it is progress.

We have not been simply waiting the last two years. Arguments and ideas have matured. We want to give you an update. In Section 1 of this post we discuss the novelty of our propositions. In Section 2 we address three of the most common objections. In doing so, we draw on all the recent work by our group thus providing an updated view on our theory.

What is new?

We have described a new and significant source of potential energy governing atmospheric motion. Previously, the only such recognised energy source was the buoyancy associated with temperature gradients.

Unlike the buoyancy mechanism, that applies to both liquids and gases, our new mechanism applies only to gases. Water vapor condenses and disappears from the gas phase when moist air ascends and cools. For this reason the water vapor pressure declines with height much faster than the other (non-condensable) atmospheric gases. As a result the exponential scale height hv of water vapor is markedly smaller than the scale height h of the air as a whole, hv << h. What are the implications of these two different scales for atmospheric dynamics?

In hydrostatic equilibrium the vertical pressure gradient force -∂p/∂z balances the gas weight in a unit atmospheric volume -ρg: -∂p/∂z – ρg = 0, where p is air pressure, ρ (kg m−3) is air density, and g is acceleration of gravity. In the absence of condensation in a circulating atmosphere the relative partial pressure γi ≡ pi/p of the non-condensable atmospheric gases, including the unsaturated water vapor, is independent of height. In hydrostatic equilibrium for such gases we have:

where pi and Ni (mol m−3) are partial pressure and molar density of the i-th gas, respectively, R = 8.3 J mol−1K−1 is the universal gas constant, and N and M are the molar density and mean molar mass of air as a whole.

This relationship determines that in hydrostatic equilibrium any work -w∂pi/∂z performed by the vertical partial pressure gradient per unit time per unit atmospheric volume is compensated exactly by the work -wγiρg performed by the force of gravity that acts on a corresponding molar share γi of the air mass (here w is vertical velocity). In other words, all work performed by the non-condensable gases as they ascend and expand is fully spent on elevating their respective molar shares of total air mass in the gravitational field. Nothing is left to generate kinetic energy.

By contrast, if we consider the saturated water vapor, condensation means that we have

That is, the work of the partial pressure gradient of water vapor greatly exceeds what is needed to overcome gravity. The main physical statement behind our new view is that this net remaining power q (W m−3)

is available to generate kinetic energy and drive the Earth’s atmospheric dynamics. Roughly speaking it is the power that remains after the water vapor has “lifted itself”. The value of q represents the volume-specific power of the “motor” that drives the atmospheric circulation.

The formation of strong vertical winds is directly inhibited by the atmosphere’s condition of hydrostatic equilibrium. For that reason the dynamic power of condensation is mostly translated into the power of horizontal pressure gradients and winds:

Here v = u + w is air velocity, u is horizontal and w is vertical air velocity, and ∇p is the pressure gradient, all measured on the circulation largest spatial scale. The kinetic energy generated by horizontal pressure gradients dissipates in smaller-scale eddies and ultimately converts to heat.

By integrating (3) over height z and noting that wN = wp/(RT) is independent of z to the accuracy of γ (e.g., see Appendix here), we obtain a relationship indicating that the driving power Q per unit area is proportional to precipitation P (mol m−2 s−1):

where T is the mean temperature in the air column, and P ≡ wNγ(0) = wNv(0) is the upwelling flux of water vapor (mol m−2 s−1), which, in the stationary state and assuming complete condensation, is equal to the downward flux of precipitating water. As discussed in our paper, this equation is exact for a horizontally isothermal atmosphere. In the general case it may be imprecise by about 10% (Makarieva, Gorshkov, 2010).

We can now compare our theory with observations. First, we note that the mean global power of atmospheric circulation estimated from (5) is about 4 W m−2, which is in close agreement with the best observational estimates. We note that this is the first and only theoretical estimate of the power of global circulation currently available. We return to this in the next section.

We then observe that the above physical relationships apply to circulation phenomena characterized by notably different spatial and temporal scales. For a steady-state global-scale pattern (e.g., Hadley cells) the mean value of precipitation P is determined by solar power I. About one third of solar power is spent on evaporation. Given that evaporation and precipitation must be nearly equal (in a steady state) we can see that P ∼ I/Lv, where Lv (J mol−1) is the heat of vaporization. In a much smaller and short-lived circulation system, like a hurricane or tornado, that moves as a whole with velocity V, precipitation within the circulation area is determined by the flux of water vapor imported. It thus depends on the height hh and radius r of the circulation, velocity V and the ambient amount of water wapor: P ∼ (hh/r)VNv (here Nv is the mean ambient molar density of water vapor).

As we can see, the physical determinants of precipitation are very different. E.g., hurricane P can be several orders of magnitude higher than the mean global P. The horizontal scale of Hadley cells is several times larger than that of hurricanes. Despite such different scales, physical determinants of condensation intensity and drastically varying P values theoretical estimates (3) and (5) successfully describe the Hadley cell as well as much more compact and transient circulation phenomena (see (Makarieva, Gorshkov, 2011) and (Makarieva et al., 2011) for details). Our approach thus provides a unified physical explanation to atmospheric circulation phenomena previously considered unrelated.

The controversy

Thanks to help from blog readers, those who visited the ACPD site and many others who we have communicated with, our paper has received considerable feedback. Some were supportive and many were critical. Some have accepted that the physical mechanism is valid, though some (such as JC) question its magnitude and some are certain it is incorrect (but cannot find the error). Setting aside these specific issues, most of the more general critical comments can be classified as variations on, and combinations of, three basic statements:

1. Current weather and climate models (a) are already based on physical laws and (b) satisfactorily reproduce observed patterns and behaviour. By inference, it is unlikely that they miss any major processes.

2. You should produce a working model more effective than current models.

3. Current models are comprehensive: your effect is already there.

Let’s consider these claims one by one.

Models and physical laws

The physical laws behind all existing atmospheric circulation models are Newton’s second law, conservation of mass, the ideal gas law and the first law of thermodynamics. Here the first law of thermodynamics is assigned the role of the energy conservation equation (see, e.g., McGuffie and Henderson-Sellers 2001, p. 1084). However, while equilibrium thermodynamics allow the estimation of the maximum possible mechanical work from heat it provides neither information about the actual efficiency of converting heat to work (kinetic energy) nor whether such conversion to motion actually occurs. In practice, this means that models do not define these factors from physical principles but through adjusting model parameters in order to force it to fit observations (i.e., to produce the observed wind speeds). Mostly this pertains to the determination of the turbulent diffusion parameters. An
interested reader see p. 1776 of Bryan and Rotunno (2009) for a simple example (see also here for a discussion). The principle remains the same even in the most complex models.

Thus, while there are physical laws in existing models, their outputs (including apparent circulation power) reflect an empirical process of calibration and fitting. In this sense models are not based on physical laws. This is the reason why no theoretical estimate of the power of the global atmospheric circulation system has been available until now.

The models reproduce the observations satisfactorily

As we have discussed in our paper (p. 1046) current models fail when it comes to describing many water-related phenomena. But perhaps a more important point to make here is that even where behaviours are satisfactorily reproduced it would not mean that the physical basis of the model are correct. Indeed, any phenomenon that repeats itself can be formally described or “predicted” completely without understanding its physical nature. We just need our experience to predict that in winter the days will be shorter than they were in summer. Thus, improvements in performance may be caused not by the correct physics but by an ever more refined description of the probability distributions characterizing persistent, regular behaviours. Consider for example how satellite data have made it possible to better analyze hurricane tracks allowing to judge about hurricane motion with some certainty a few days in advance, something entirely unavailable for the ancient weather forecasters. Such information is definitely valuable and useful. But it does not provide any insight concerning outcomes when the underlying system undergoes changes. For example, a climate model empirically fitted for a forest-covered continent cannot inform us about the climatic consequences of deforestation if we do not correctly understand the underlying physical mechanisms.

You should produce a better model than the existing ones

Modern numerical models of weather and climate are over half a century old. They contain huge numbers of parameterizations that summarize the work of thousands of researchers working for decades. As already mentioned, these parameterizations include the many adjustments needed to match the behaviour of the model to reality. If the physical core of the model is changed (e.g. from buoyancy- to condensation-driven), all these parameterizations will require revision. To expect a few theorists, however keen, can achieve that is neither reasonable nor realistic. We have invested our efforts to show, using suitable physical estimates, that the effect we describe is sufficient to justify a wider and deeper scrutiny. (At the same time we are also developing a number of texts to show how current models in fact contain erroneous physical relationships (see, e.g., here)).

Your effect is already present in existing models

Many commentators believe that the physics we are talking about is already included in models. There is no omission. This argument assumes that if the processes of condensation and precipitation are reproduced in models, then the models account for all the related phenomena, including pressure gradients and dynamics. This is, however, not so. Indeed this is not merely an oversight but an impossibility. The explanation is interesting and deserves recognition – so we shall use this opportunity to explain.

The circulation “motor” q unambiguously defines condensation intensity S that enters the continuity equation (see also Gorshkov et al., 2012). In a horizontally isothermal atmosphere for an arbitrary unknown condensation rate S the continuity equation has the form (see (A7) on p. 1053 in the paper)

where S and Sd are in mol m−3 s−1, Nd and γd are the molar density and the relative partial pressure of the dry air constituents. Recalling that in hydrostatic equilibrium q = -u∇p = RT(u∇N) (4) and using (3) we obtain from (6)

which the reader may recognize as the (in some quarters, notorious) Equation 34 in the paper. The main message from the above derivation is that the relative difference between S and Sd is itself of the order of γ: (S – Sd)/γd = S = q/(RT).

In current models in the absence of a theoretical stipulation on the circulation power, a reverse logic is followed. The horizontal pressure gradients are determined from the continuity equation, with the condensation rate calculated from the Clausius-Clapeyron law using temperature derived from the first law of thermodynamics with empirically fitted turbulence. However, as we have seen, to correctly reproduce condensation-induced dynamics, condensation rate requires an accuracy much greater than γ << 1. Meanwhile the imprecision of the first law of thermodynamics as applied to describe the non-equilibrium atmospheric dynamics is precisely of the same order of γ. The kinetic energy of the gas is not accounted for in equilibrium thermodynamics.

It is an interesting situation. The precision of the first law of thermodynamics is sufficient to determine condensation rate to the accuracy of γ. This accuracy is more than sufficient to allow existing models to be fitted to reproduce realistic precipitation rates. But at the same time the precision provided by the first law of thermodynamics is in principle insufficient to quantify our condensation-induced dynamics. This two-faced result is striking and has implications for models: Suppose that a modeller develops a model of atmospheric circulation that assumes that heating rate gradients are the only driver. If this model presents some unrealistically high wind velocities (due to some unanticipated effect) then this behaviour can readily be suppressed with only minor modifications. The model can thus accommodate phenomena for which it lacks any intrinsic relationships without any red-flags being raised.

We showed in our paper that following this route (i.e., reproducing condensation dynamics from condensation rate) requires a thorough theoretical analysis of the condensation rate behavior (see Section 4.2 and Appendix in the paper). As we discussed, no adequate theory for condensation rate exists in the current models. Therefore, as the fitting process cannot anticipate all situations (combinations and/or values of key variables etc.) there must be occasions when the omission of the relevant physical processes is revealed. The pertinent example here is in the analyses of alternative parameterizations of condensation rate: applying different cloud microphysical parameterizations in hurricane models produces systems that differ from each by over 40 mb in their central drop of pressure (with 55 mb being the mean figure for the pressure drop in hurricanes) (e.g., Deshpande et al. 2012). Generally, the situation is such that condensation-induced dynamics are neither present in modern models nor have their impacts been studied in an adequate manner.

Summary and outlook

The Editor’s comment on our paper ends with a call to further evaluate our proposals. We second this call. The reason we wrote this paper was to ensure it entered the main-stream and gained recognition. For us the key implication of our theory is the major importance of vegetation cover in sustaining regional climates. If condensation drives atmospheric circulation as we claim, then forests determine much of the Earth’s hydrological cycle (see here for details). Forest cover is crucial for the terrestrial biosphere and the well-being of many millions of people. If you acknowledge, as the editors of ACP have, any chance – however large or small – that our proposals are correct, then we hope you concede that there is some urgency that these ideas gain clear objective assessment from those best placed to assess them.

JC comment: This is an invited guest post, which follows up on Makarieva et al.’s previous blog post at Climate Etc. Comments will be strictly moderated for relevance and for civility.

1,404 responses to “Condensation-driven winds: An update”

Condensation of steam causes pressure drop (when water turns into steam, it occupies about 1600 times the volume, at standard temperature and pressure). This was the first industrial steam-powered device (developed in 1698 by Thomas Savery), It used a (partial) vacuum from condensation to raise water from below, then used steam pressure to raise it higher.

Much of this discussion has been about theory. Our paper and our blog were about theory too – so that makes sense. But I suspect many readers are interested in evidence. Dr Held too asked for “evidence” to pass his “high bar” – we rejected the argument as a point of principle. The question at issue then was whether we had presented a case coherent and interesting enough to answer: it is a theory. Theories come first the evidence comes later.

But that does not mean we don’t have extraordinary evidence.

We wrote a little about this in the paper (most points below can be explored by looking at the reference list there or at http://www.biotic-regulation.pl.ru/index.html), but it may be useful to highlight a few again here so you can make your own assessments. What is our evidence so far? How does out theory match reality?

For me the most powerful evidence comes from looking at how rainfall varies as we travel inland from the coast (over relatively flat terrain): Why does rainfall not decline over forest? It declines over non-forest in a relatively constant manner that is easy to understand (This seems to be a global pattern: see the figure in my previous blog here http://judithcurry.com/2011/03/30/water-vapor-mischief-part-ii/). Recycling is not an explanation – it would reduce the rate of decline but it could not prevent it. There is no alternative explanation at present.

This effect – the drawing of rain into continental interiors – requires a biologically functioning forest so we would predict that the effect will be smaller over boreal forests in deep winter (when the forests are metabolically inactive and not transpiring moisture). Observations support these predictions. There is no alternative explanation at present. See, e.g. Makarieva, A. M., Gorshkov, V. G., and Li, B.-L.: Precipitation on land versus distance from the ocean: evidence for a forest pump of atmospheric moisture, Ecol. Complex., 6, 302–307, 2009.

Our paper (discussed in this post) shows that we can estimate the power of global atmospheric circulation. This is the first ever such estimate developed from first principles and, though intended as a rough estimate, is remarkably close to the measured values. No alternative theory can currently explain this value.

Where we have good data on forest loss and rainfall change there are some observations suggesting a regional decline in rain regularity (as we would predict). See E.g. Webb TJ, et al. 2005. Forest cover-rainfall relationships in a biodiversity hotspot: The Atlantic Forest of Brazil. Ecological Applications 15: 1968–1983.

The work by Anastassia and co. (not me!) on hurricanes is also impressive: it shows that the condensation generated pressure gradients can give a physically and analytically consistent model of how such storm systems function and can be used to estimate several characteristics from first principles. E.g. Makarieva, A. M. and Gorshkov, V. G.: Condensation-induced kinematics and dynamics of cyclones, hurricanes and tornadoes, Phys. Lett. A, 373, 4201–4205, 2009.

So the score-card so far is 7:nil in favour of our theory (I rate the hurricane work as three points … but even if you don’t 5:nil is a good margin). That’s a good score line. Extraordinary? Well I acknowledge too that the search for counter-evidence is in its infancy.

So now the theory can and should be tested further. All those who think it is right, all those who think it is wrong and all those who are uncertain but recognise why it matters, can I hope agree that the ideas should be tested. That is a shared goal.

Finally the potential energy of the atmosphere is being considered. The observed reduction in the height of the atmosphere is the work available to the earth that moves energy from the upper atmosphere to the warmer surface. Temperature of the stratosphere decreases and surface temperature and sea level rise.

Please take note that the first three equations in the post summarize the key points. The effect is based on the difference in the vertical scale heights h and hv of saturated water vapor and whole air, respectively. This difference exists independent of whether the atmosphere is adiabatic or not. In fact, it becomes larger if the temperature lapse rate grows (i.e. when it is 6.5 K/km rather than moist adiabatic).

Please correct me if am wrong. In the first term of the Equation (3) above and for q, you considered energy of air pressure and that of gravity for an arbitrary air parcel and no sensible heat from the surroundings. Therefore, you inherently made the assumption of adiabatic process without justification. You must prove that it is an adiabatic process.

Perhaps. The lower the estimates of climate “sensitivity” become though, the greater it would increase in significance. What actually happens in the moist air portion of the atmosphere in any case is significant and obviously not handled very well in the current generation of climate models. Unless of course you choose to cherry pick one or two, here and there :)

‘We may believe, for example, that the motion of the unsaturated portion of the atmosphere is governed by the Navier–Stokes equations, but to use these equations properly we should have to describe each turbulent eddy—a task far beyond the capacity of the largest computer. We must therefore express the pertinent statistical properties of turbulent eddies as functions of the larger-scale motions. We do not yet know how to do this, nor have we proven that the desired functions exist’. Thirty years later, this problem remains unsolved, and may possibly be unsolvable. ‘ http://rsta.royalsocietypublishing.org/content/369/1956/4751.full

The scale issues for these processes preclude computation and the statictical functions are unknown and perhaps unknowable. Energy approaches seem reasonable.

Pekka Pirilä: Perhaps I should have said that based on the above I agree with them who say that the effect is there but is small and adds nothing significant to the standard theory.

Globally, the effect is approximately the same order of magnitude as the hypothesized CO2 doubling effect on climate. There are a lot of such small cavities in the standard theory, and collectively they may overwhelm the small CO2 effect. For that reason, your judgment of “adds nothing significant” is premature.

What happens is that evaporation adds water vapor to air increasing it’s volume. That moist air rises ans loses gradually that water vapor resulting in precipitation. When that’s over the volume is back to the relatively dry air volume. The only consequence of that all is that the speed of the uplift has to be just a tiny bit higher than otherwise.

Pekka Pirilä: Perhaps I should have said that based on the above I agree with them who say that the effect is there but is small and adds nothing significant to the standard theory.
…………….. later ……………….
There’s no extra effect.

I had some initial reactions on the paper. They were not very definitive but the basic idea was the same that i now see much more clearly.

What’s wrong with the paper is that they do not not discuss properly the mechanisms in the atmospheric context where pressure is one independent variable. It’s a control variable, not the outcome. The way they obtain pressure gradients does not make sense because of this.

Condensation is certainly there and it’s important because of the release of latent heat, but the loss of gas molecules is compensated automatically by rather small vertical adjustments in the atmosphere and does not drive anything of the kind the paper proposes.

That moist air rises and loses gradually that water vapor resulting in precipitation.

Will you please elaborate on that sentence for me? My comprehension is that a rising moist air parcel reduces in temperature and volume gradually, but condensation occurs rather abrupt when the air parcel temperature reaches the dew point. That would be the reason for flat-bottomed clouds, no? Thanks.

The paper is about the phase where air has reached saturation. When saturated air cools part of the water condenses and the air remains saturated at the lower temperature. (In real atmosphere the air gets a little oversaturated, but for this consideration it can be thought that oversaturation is not possible.)

The flat bottom is related to condensation temperature. The supersaturated condition should be fairly common since dust or some particle is generally need to start condensation.

The typical southern afternoon clouds form and build in patches even though the humidity is pretty uniform. If you consider only the saturation vapor pressure, as water condenses there would be a pressure differential so water vapor would flow toward the condensation. Since precipitation is not a given, the condensate flows out level with the condensation temperature. That is the way I understand what the authors are saying which is not all that exciting.

What could be exciting is that if the individual water saturation pressure can be consider independently of overall atmospheric pressure, they you could predict how clouds would form more reliably and what extreme energy potential is possible. An inch or two of pressure differential is pretty impressive with the right area.

Pekka, yes, I came to a similar conclusion when this paper was first out. The latent heating from condensation raises the pressure by an order of magnitude more than the vapor loss decreases it. In an ascending condensing air parcel, this pressure rise leads to expansion, reduction in density, and buoyancy. It has the reduced density more because it is warmer, not so much because it lost some vapor.

Thank you for your comment. Perhaps you might wish to clarify. Heat cannot be compared to volume of gas, they have different physical units, one cannot be larger than another. We might need to think of some realistic physical process where both effects of condensation are manifested and judge their significance from measurable parameters.

In our work we show that the effect of removing a little of gas produces a significant dynamic power. Similar estimates for latent heat are lacking in the meteorological theory, and the difficulty associated with obtaining such estimates was appreciated by people early in the first half of the 20th century.

You may be making valid points, but I am not sure I see how they are related to the problem in question. Heat affects temperature, ok, but winds are driven by pressure gradients (as per Newton’s second law). Note — not by temporal pressure changes, but by spatial pressure changes. What kind of pressure gradients are produced by latent heat? I’ll tell you in advance that there is no answer to this question in meteorological textbooks. And the reason is physically clear.

There’s is no reason for the very small loss of gas would create significant pressure effects. The little it does goes against the much stronger effect through the influence on temperature.

The claim that vertical movements of gas could not compensate the changes from loss of gas molecules lacks all justification. The whole phenomenon is related to vertical movement of gas and changes that very little. There’s nothing that would make that difficult and require some strong winds.

The phenomena discussed in the paper are such detail issues that they are probably in some way included in meteorological models. How well the modelers succeed in modeling the details is seen in the success of weather forecasts (and lack of it when too much is expected). Climate models do not go to such details but use parametrizations based only indirectly on physics fundamentals.

It’s official: our controversial paper has been published. After a burst of intense attention (some of you may remember discussions at Climate Etc., the Air Vent and the Blackboard), followed by nearly two years of waiting, our paper describing a new mechanism driving atmospheric motion has been published in Atmospheric Chemistry and Physics.

Has the paper been altered to address the criticisms raised in earlier discussions? If so, could we get a brief explanation of the response to that criticism?

‘Roughly speaking it is the power that remains after the water vapor has “lifted itself”. The value of q represents the volume-specific power of the “motor” that drives the atmospheric circulation.’

Colour me skeptical. I am assuming that this power is the enthalpy of condensation and is dissipated radiatively higher or lower in the atmosphere with the height largely determined by the momentum of the rising air mass.

Coastal winds are driven more by temperature differences between land and ocean. They happen where there is desert and forest – although both do influence the availability of moisture in the atmosphere and therefore precipitation and dew.

Hadley cells are driven by temperature differentials between the equator and higher latitudes. Walker Circuklation is driven by ocean temperature differentials in the Pacific equatorial region. Polar cyclones are caused by planetary rotation. Tropical cyclones are spun up by Coriolis forces.

Chief, the main thing to me seems to be cloud formation. If the the air is saturated it is saturated, why does there need to be an aerosol factor? By setting c=cs they are looking only at a 100% relative humidity condition. If a cloud doesn’t form then because of lack of aerosols to start formation, chill that sucker down some more to form ice crystals and it should make its on substrate to form. Add aerosols and you reduce the energy required to initiate condensation i.e., form clouds.

If CO2 or anything else causes surface warming which in turn increases the ethalpy moist air, that would change the temperature required for saturation. More water means condensation starts at a higher temperature, lower altitude. Lower altitude, higher density, the clouds can absorb more energy producing an increase in “upper” level convection with a greater likelihood of mixed phase clouds. Which can result in hailstone or ice crystal recycling, basically an atmospheric heat pipe. Leading to all sorts of neat stuff potentially, like say SSW events and ozone depletion.

Trendberth BTW, missed 20Wm-2 that is associated with clouds and surface energy absorption. Of course, he is just a scientist, not an HVAC engineer :)

I have no clue if this group has figured all that out, but there are some serious flaws with the application of radiant physics on a chaotic water world.

It was indeed a curious publication process. The editor in his publication statement said:“the editor concluded that the revised manuscript still should be published – despite the strong criticism from the esteemed reviewers…”
…
” the handling editor (and the executive committee) are not convinced that the new view presented in the controversial paper is wrong.”

So the editor invited the esteemed reviewers (and in at least one case, some persuasion required) to give their views, and then said he didn’t believe them, but gave no reasons.

The reason for peer-review is to ensure quality, to make sure that the papers have been critically read before being published (by fresh sets of eyes), and to prevent the most obvious forms of cronyism.
We know that is small fields it is impossible to prevent cronyism anyway.

I see no problem with the editor doing THEIR job and making the final decision and then letting science work the way is is supposed to work. We have enough gate-keeping as is. I’m surprised that Mosher in particular is worried about the reviewers given their experiences with the BEST paper. This took 2 years, so the decision to publish anyway was not taken lightly. They did not disregard the reviewers comments. In fact, they published a special note, thus ensuring that this paper will get a LOT of scrutiny from the readership. Considering the butt-loads of crap published in all kinds of fields, not sure why this one should be excluded because it is a different way of looking at a problem. That does not usually keep papers from being published.
It’s a journal, not the Vatican.

I remember the blog discussion from the Air Vent in 2010 and the comments at the ACPD site. You may be correct that this has been a curious review process. The only thing more bizarre however was the fierce opposition to the discussion paper, and your comments still stand out. I believe that it was in part the nature this opposition that influenced the decision to publish this paper. A case of “methinks the lady doth protest too much”.

It was also this unusual opposition that drove me to conduct some simple empirical experiments back in 2010. I found that all that it would take for the Markarieva Effect to work would be for a rising moist air mass to be slightly more diabatic than a dry air mass. This of course would be the case because a rising moist air mass is full of radiative gases that can emit as IR some of the latent heat released during condensation.

I now believe that is why the paper had to be trashed. It was getting too close to the main role of radiative gases in atmospheric circulation, both horizontal and vertical. After being driven to physical experiment by the thousands of comments, wholly unsupported by empirical evidence, on the M2010 discussion paper, I have continued to experiment in convective circulation in gas columns in a gravity field.

I have found that without radiative energy loss from the atmosphere at altitude, convective circulation stagnates. When convective circulation stagnates in a gas column heated at the base, the gas column heats. The gas column can be heated and cooled a separate locations at the base, but it will still run hotter than a gas column heated at the base and cooled higher up.

This is the critical role of radiative gases in convective circulation, energy loss at altitude. Without radiative gases, strong vertical convection below the tropopause would stagnate and our atmosphere would heat. Radiative gases cool our atmosphere at all concentrations above 0.0ppm. Adding radiative gases to the atmosphere will not reduce its radiative cooling ability.

Nick, I may not have found this out if not for your opposition to the M2010 discussion paper.

Here is a diagram to illustrate that point –

The figure on the left shows normal convective circulation occurring. As you can see radiation of IR to space is critical to this continued circulation. The figure on the right shows what would happen shortly after the atmosphere lost its ability to radiate IR. Convective CIRCULATION “stalls” or stagnates, and the atmosphere heats. (this is just before the atmosphere goes isothermal and surperheats)

Manacker,
Yes, I am making a direct challenge to the failed hypothesis that radiative gases create a greenhouse effect in our atmosphere. Those proposing that CO2 emissions will heat our atmosphere do so on the basis of critically flawed equations. The “basic physics” of the “settled science” never correctly modelled the role of radiative gases in tropospheric vertical convection. They never modelled a moving atmosphere, or the role of gravity in biasing conductive flux between the surface and atmosphere. (the surface is more effective at conductively heating the atmosphere than conductively cooling the atmosphere).

It is said that extraordinary claims require extraordinary evidence. The AGW hypothesis essentially is an extraordinary claim that adding radiative gases to the atmosphere will reduce its radiative cooling ability. To date no supporting extraordinary evidence has ever been produced. What the M2010 incident shows is not only did some of the AGW promoters know their hypothesis was rubbish, but they have known for years.

Well, Douglas, they weren’t addressed, and there are many. But let me take just one. The assumption that, in the heading of Appendix A1:
“Linearity of condensation rate over the molar
density Nv of water vapor”

It was point five in my first discussion entry. It’s still here, and emphasised; the equation is S = CNv.

Now physically this is nonsense. There’s always some humidity, but it mostly isn’t raining. Condensation doesn’t occur at all until Nv nears saturation.

The justification given is the first order molecular kinetics of condensation. But this is wrong for several reasons. First it ignores the back reaction, evaporation. In unsaturated air, that is faster, so you get no condensation at all.

Secondly, no time scale is mentioned. In fact, these are nano-second scale reactions. If S = CNv really did apply, the atmosphere would dump its water on that time scale.

Of course it can’t. That’s the problem with naive kinetics. You have to look for the rate limiting process. And with condensation, it’s usually the rate of removal of latent heat. On the scale of the atmosphere, that takes many seconds to hours. Molecular kinetic issues are insignificant.

I agree 100%. The bulk of the atmosphere, N2 and O2 are the real GHGs. The radiatively active gases cool the atmosphere by radiating the atmospheric energy to space, just like roof windows in a greenhouse.

Edim,
Bingo. N2 & O2 are the true “greenhouse” gases . H2O and CO2 are the broken panes in the greenhouse. There will of course be a backlash from the defenders of the “cause” to increased discussion of this. Watch out for “baffegab”. If you see direct linear flux equations being used for modelling do not be snowed. Unless you see a complex program running such equations iteratively on discrete moving air masses you are not seeing correct modeling of the role of radiative gases in our atmosphere. You have it right. I suspect you are an engineer. If so you will know to question yourself, always check your work and anticipate that you may make errors. What you may not know is that other less ethical people exploit this to make you doubt yourself. They pose as as a “consensus”, they pretend to be many voices. This is the Alinsky technique. There are actually far fewer supporting the Knights of Consensus than you may think. They can be stopped. Science can be saved.

Nick I don’t think the editor has said he doesn’t believe the reviewers just that they shouldn’t be the last word on this subject. The authors accept that they shouldn’t be the last word, encouraging further debate and criticism, there is no reason why the reviewers can’t also take such a reasonable position.

But what is the point of having a review then? Why not just publish whatever comes in? In the interests of further debate and criticism?

But then again, what does “accepted” mean? The paper is already available for reading. Accepted should mean someone thinks it OK. Not the reviewers. And if the editor has some reason for thinking so, he isn’t saying.

Nick
I agree the editor’s message is unusual and the delay was atypical — but it does look like the peer review process did what it was meant to do. It gathered feedback including significant criticisms from acknowledged experts. We (the authors) responded in detail to each and revised (i.e. improved) the paper to reflect all the inputs. Then the editor made a judgement. They were asking themselves if there was sufficient grounds to reject the paper: it appears they were unconvinced. I presume they weighed all the reviews, replies and changes — then they took the decision that is theirs to take. That all seems normal.

You are a publishing scientist right? I’m sure you acknowledge that papers that are eventually accepted often receive harsh harsh criticisms at some stage in the review process? That is normal. The authors can then defend, adapt the paper, and/or appeal. That is all quite normal. In our case this is all online so you can of course form your own opinions. But the editor is the final judge — they are not required to write a detailed assessment. That too is normal.

What is unusual is the fact that this time the editor offered any explanation at all. I don’t think I have ever seen that before.

From the EGU.eu website
” after having passed a rapid access peer review process manuscripts submitted to EGU two-stage-journals will be published first of all in the “Discussions” part of the website of that journal being then subject to interactive public discussions initiated by alerting the corresponding scientific community. The results of the public peer-review and of the interactive public discussions are then used for the final evaluation of the manuscript by the Editor and, eventually, for its publication on the website of the actual journal.”

Nick it’s not just the reviews but the whole ‘discussion’ that the editor takes into account when deciding whether to publish. Presumably the editor believed the responses the author gave to the criticisms had some merit. And just like an author knows that their work may be deemed to have merit or not surely a reviewer also knows that their criticisms and recommendations may be deemed to be strong enough to block publication or not. A reviewer is not given absolute power in these situations. From my reading of the rules the reviewers comments (and the wider discussion) are a tools to be used by the editor, who has the final say. I’m sure in most cases editors give great weight to reviewers words and they know they are risking antagonizing them if they don’t, so I guess the decision isn’t taken lightly.Isaac Held from what I’ve seen from his blog responses seems like a fairly level headed person, I’m sure he can shrug off this ever so slight prick to his ego. BTW the editor doesn’t seem like some idiot him self (http://nenes.eas.gatech.edu/CV.pdf).

HR,
It’s a paper of mathematics and physics. People in the Journal discussion and at blogs have pointed to shortfalls in the mathematics and physics. There is essentially no mathematical defence of the work by anyone other than Dr M. If Dr Nenes has something to say about why the mathematics is “not wrong”, I think he owes it to the reviewers that he invited, and to the journal readers, to say what it is.

Nick “shortfalls in the mathematics and physics” — we acknowledge your various comments have been helpful in pinpointing areas needing clarification but as far as I can see your points were addressed. We answered each. That helped us which we acknowledge. If you are not satisfied please be specific — I am assuming you have seen all the changes and replies (additional appendix etc). I know it takes time and energy but we do appreciate the efforts.
Many thanks

I think Eli made the best point the other day. Who in their right mind would review again for this journal?
For the most part i think most scientists will just ignore the work, but the reviewers are the ones who have been ‘harmed’ here.

“steven mosher |”but the reviewers are the ones who have been ‘harmed’ here”

I hope not. This looks like an issue that Judy is well placed to answer (as one of the harmed referees). Active publishing researchers are engaged in these kind of debates on a daily basis and most develop fairly thick skin — and in this case there was never a hint of disrespect to anyone.

Do you suggest that a journal process should never contradict a referee? Or that journals should set aside their editor’s independence to attract referees? Its an idea, but it might discourage researchers with novel ideas from submitting their ideas.

This is a good place to highlight again how grateful we were to the referees. We welcomed their feedback. We have said it before and repeat it again.

We knew in advance that Dr Held was likely to be critical (he has published work that assumes very different atmospheric mechanisms) but we also recognised that critical scrutiny would be good for the paper (held us sharpen up the logic, spot flaws etc). Each and every technical point Dr Held made was addressed in our responses. You can see our replies at the APCD site. We specifically reviewed the study by Spengler et al. (2011) that Dr Held holds as a comparison to ours and we explained the flaws in its physics (see http://www.atmos-chem-phys-discuss.net/10/C14894/2011/acpd-10-C14894-2011.pdf). We also argued why our ideas should not be given a “higher bar” than conventional ideas — even though that may seem reasonable at first glance (See http://www.atmos-chem-phys-discuss.net/10/C15085/2011/acpd-10-C15085-2011.pdf).

To expand a bit. It is unusual, but not unknown that an editor will publish against the advice of anonymous referees, or that a grant will be funded that does not score well. However, doing so when the names and reviews of the referees are public is not going to be taken well by anyone approached by Nennes to do a review. Even JC’s review did not endorse the paper, merely saying that it was interesting but flawed.

By adopting the open review process, the EGU took on a heavier obligation to the reviewers.

To give some detail concerning the peer-review process in EGU: the reviewers may decide if they publish their review anonymously or not. The reviewers are not obliged to reveal their names. Since all the correspondence concerning the paper between the Editors and the reviewers is privileged, there is no difference in this aspect with the conventional procedure.

Eli “Even JC’s review did not endorse the paper, merely saying that it was interesting but flawed.”
Can you point out where she said it was “flawed”? I was a little confuse so just checked back and didnt see that.
I thought she was encouraging. She said “The paper is interesting and provocative, and these ideas should be developed.” and made four specific suggestions where we could strengthen our case — each of which we responded to. She certainly appeared to think it was a potentially valuable contribution.

Douglas, the “harm” done to reviewers can take on many forms, not merely disrespect. For example, based on this this experience folks might look at reviewers differently than they did before. For example, I now have to choose.
1, was the editor mush headed
2. Was reviwer X an ineffective critic.
in one case the editor suffers a harm in the other case the reviewer suffers.
I think Eli’s point stands and I haven’t seen any credible challenge to it.
So help me out here. Explain to me why Eli is wrong. Another point. Basically the reviewers wasted their time. Since we rely on them to do science, those of us who pay their salaries have an opinion on this.

Willard
(greetings again)
I don’t know if you have done much reviewing but I would judge that a positive review if I had written it. These four issues were all specific constructive points – stated clearly. You offer what you think is needed to improve it and you expect the authors to address these (or explain why not).
My concern here is the use of the word “flawed” which may have a rather damning flavour which I did not see in the review. I guess by your criteria every paper every subjected to a rigorous review will now be called “flawed”. I used the word differently — if I was a reviewer and called a paper “flawed” I don’t think I would offer a clear list of fixes. Maybe it is simply a question of language.

Steven Mosher — Well if my previous answer didn’t help, and you require everything to be so clear cut that researchers cannot disagree unless one or other is “mush headed” or “ineffective” I am not sure I can persuade you. The world of science I live in is very different: it thrives on the dynamic of contrasting ideas and competing theories — that is a positive force. We seek out criticism and feedback because that is what drives us forward and keeps us from dogma. I don’t look for “mush headed” or “ineffective” critics I look for the ones I admire and respect. So I don’t recognise the scenario you offer. In Ireland we argue for the fun of it too … kind of banter — but it is also a way to engage and probe people’s ideas and I would often play the devil’s advocate simply to see where the argument goes and what we can learn. But certainly it is different in other cultures … maybe what you are used to is very confrontational.
If you think it is a key point perhaps the best option is to ask Dr Held and Dr Curry. You, Eli and I are simply speculating. We don’t know.

Science must be open to new ideas but it must also take into account what has been learned earlier. When anyone proposes that there are major faults in the earlier knowledge she or he cannot expect that others pay much attention to that unless sufficiently evidence is given on the significance of the new findings and on that the new approach does not contradict earlier confirmed knowledge.

Atmospheric physics has been studied and its understanding has been developed by innumerable scientists over long period. Jumping in and claiming that a mechanism that is well known but considered a very minor factor would actually be very important and require major changes in thinking is something that requires solid arguments in a well organized form that answers clearly the obvious questions. A paper that falls severely short of that is not worth publishing.

Pekka Pirilä
Hmmm so certain? No doubts at all?
Let’s try a thought experiment please. Imagine a world where our theory is correct but few know it as they like the theory they have. You are on our team, you know the theory makes good sense, and you are keen to get the ideas accepted. Together we publish the physical reasoning and various evidence and write papers highlighting the gaps and flaws in the conventional ideas. Now … just for the sake of argument how should we then convince a sceptic that our theory is worth engaging with (not believing necessarily but accepting it as a reasonable possibility worth testing or evaluation). Be as specific as you can. How should we do that in our imaginary world?

Your problem is totally in that you have not presented evidence at a level that would convince others.

There’s nothing new in your basic physics. Thus everybody accepts that. What you must do to get accepted is to put the physics in full context and analyze extensively enough the behavior of the large scale atmospheric phenomena. With the present level of evidence people don’t believe you and they never will, if you don’t provide the relevant evidence. Nobody else needs to care as long as they are not convinced at all of your claims.

The tools are there in the atmospheric models. If you cannot use them that’s your problem. You cannot expect that others would bother until you have given evidence accepted by them.

Mosher your assumption here seems to be that all concerned here are fragile flowers and the whole process is ego driven. The clue for all concerned is that the process is OPEN. This is a fact not hidden from anybody. If the reviewers can’t handle their opinion being challenged in an open manner they shouldn’t be reviewing for EGU. If the reviewers fail to read the rules of the EGU review process and feel harmed by judgements that fall within those rule then they shouldn’t be reveiwing for EGU.

It’s clear this review process is unusual but the editor has not stepped outside the EGU’s own rules. It should be pointed out the editor himself doesn’t seem like some idiot from his online CV. Mosher I think you assume the participants in this process (including the reviewers) are more fragile than they actually are, strange given your own robust style.

What difference does it make who reviews this stuff, if it is only a box checking exercise? They will probably have to recruit reviewers from the same suspects who review for G&G. If G&G does in fact have reviewers.

Willard “Your concern does not seem to be about semantics, Douglas, but about public relations”
its about both.
We wrote the paper and now the blog and hope for a rich discussion with anyone interested – so certainly we value public outreach. I guess that is what you mean “public relations”.
Accuracy matters to me in any case — as a scientist that is part of my value system. A request for clarification should not be called something else (e.g. an error or flaw requiring repair). Certainly it matters more if the work of my colleagues and myself is subject to such misrepresentation (then I have a greater responsibility to offer the correction).
Is that what you want me to acknowledge? I acknowledge it.
Hope that helps. I do appreciate the mischievous spirit but plan to focus on more substantive issues now.

[Douglas] Do you suggest that a journal process should never contradict a referee?

[Eli] It is unusual, but not unknown that an editor will publish against the advice of anonymous referees, […] However, doing so when the names and reviews of the referees are public is not going to be taken well by anyone approached by Nennes [from Georgia Tech, let it be noted] to do a review. Even JC’s review did not endorse the paper, merely saying that it was interesting but flawed.

[Douglas] Can you point out where she said it was “flawed”? I was a little confuse so just checked back and didnt see that.

[willard, quoting chapter and verse] “There are four major issues that need to be fixed before the paper is accepted for publication: […]”

[Mosh] So help me out here. Explain to me why Eli is wrong. Another point. Basically the reviewers wasted their time.

[Douglas, to willard] I don’t know if you have done much reviewing but I would judge that a positive review if I had written it.

[Douglas, to Mosh] Well if my previous answer didn’t help […] I am not sure I can persuade you.

[Let’s skip Pekka’s here, for convenience.]

[willard] I believe the quote justifies Eli’s claim. If you prefer, you can replace ‘flawed’ with ‘with four major issues that need to be fixed’. I don’t think Eli will mind.

[Douglas] I’ll consider that an agreement! Reassuring to know you can adjust your claims in the face of evidence.

[willard] Thanks. Your turn. [Eli’s claim] does not entail that the flaws were redhibitory, as you are now suggesting. Nor does it entail that Judy would need to make an adversarial comment to use the word “flaw”.

[Douglas] A request for clarification should not be called something else (e.g. an error or flaw requiring repair).

***

I wonder who’s looking the most mischievous there, Douglas. Really.

Nick’s point raised by Judy’s was not a mere request for clarification. As far as I can see, it has not been addressed, except by excusing yourselves with something like “Oh, science shan’t ask for perfection. It’s just a theory anyway.”

You got lucky, Douglas. Please don’t push it.

And right now, with me here and at Eli’s, you are pushing it. Too much defensive rope-a-dope. See how you’ve been rope-a-doping in our little chats.

I say chats in plural because it is the second time, now, in a few days. Here was the first one:

Yes, as I mentioned on the previous thread, Isaac Held rejected this, the authors gave a response via ACP, and Held never got a chance to respond before the editor accepted it. In other journals, a reviewer that rejected a paper would at least be able to tell the editor whether the responses to his review were adequate, but ACP doesn’t seem to have that second round procedure, which is very strange. The responses to Held did not address his main concerns at all, so I am sure he would have still rejected it, because the paper hardly changed from the one he reviewed.

Jim “The responses to Held did not address his main concerns at all, so I am sure he would have still rejected it, because the paper hardly changed from the one he reviewed.”
It would indeed be interesting to know what he might have said — and your analysis may be correct. But note that referees do not reject papers — they offer a case for doing so.
Let’s be specific — which point(s) in particular do you think should have led to a rejection?
Thanks

Douglas, his main reason for recommending rejection appears to be a valid one that the paper’s equations do not prove the case it is trying to make, and there is some incoherence in the arguments. Since the paper was about equations, it suffers from not successfully proving its point.

Jim D “it suffers from not successfully proving its point”
I believe we addressed each specific point that Dr Held raised. It is hard to take this discussion further without you being more specific. A theory is a theory — proof comes later and is based on evidence.

“So the editor invited the esteemed reviewers (and in at least one case, some persuasion required) to give their views, and then said he didn’t believe them, but gave no reasons.”

Nick, there are essentially two levels of criticism that a reviewer can supply, criticism of individual components or of the finished product; the model.
You might not like the model presented by the authors, but if all their steps are correct, then it should be published.
Here the authors have come up with a large number of components, which it appears stand up to mathematical and physical testing. The authors then stick them together and come to some sort of model.
A referee can find fault in the former, blocking publication. However, you can’t block a publication just because you think that a model is wrong.
It’s rather like accepting that all the components of an airplane will work, but if they are put together as suggested by the engineer the thing will still not fly. It might or it might not. If you have no empirical test, you have to let the authors give their view.

Gcm or at least the literature have a difficult task reconciling the metrics with two underlying theories of opposing signs with say synoptic storms and baroclinicity due to the reduction in meridional gradient in a warming world,and the increase of water vapor,hence life birth cycles .

Gcm cannot resolve at mesoscale levels (which is the scale length of weather systems) which makes prediction both difficult and problematic as when the coarse grain resolution is enhanced we move beyond the physical laws per se.

Nabil,
avoiding revision of GCMs was the reason many thought the Knights of Consensus were fighting so hard to trash the M2010. It may be more serious than that. All it takes for the Makarieva Effect to work is for a rising moist air mass to be more diabatic than a dry air mass. This may involve radiative energy loss. Possibly IR from all that water vapour. The Knights of Consensus cannot allow any heresy involving atmospheric circulation being driven by radiative gases so they tried to trash the paper.

many good comments can be quoted: In current models in the absence of a theoretical stipulation on the circulation power, a reverse logic is followed. The horizontal pressure gradients are determined from the continuity equation, with the condensation rate calculated from the Clausius-Clapeyron law using temperature derived from the first law of thermodynamics with empirically fitted turbulence. However, as we have seen, to correctly reproduce condensation-induced dynamics, condensation rate requires an accuracy much greater than γ << 1. Meanwhile the imprecision of the first law of thermodynamics as applied to describe the non-equilibrium atmospheric dynamics is precisely of the same order of γ. The kinetic energy of the gas is not accounted for in equilibrium thermodynamics.

I think that this paper, and the scholarly discussions addressing it, constitute a step toward filling one of the “cavities” of the science.

When wind falls down, it loses potential energy. It takes energy to raises the wind back up and maintain the circulation. Definitely, it is the latent heat of condensation that provides this energy, there is no other. The lower atmosphere is adiabatic invariant and exchanges no sensible heat with its surroundings. Th authors of the paper failed to prove that the lower atmosphere is adiabatic invariant, and this is my main critique of the paper.

so, re framing, should unconfirmed, likely wrong, inconsequential physics be put into models?
Some GCM are open source, believers should knock themselves out and stop pestering people with confusingly notated papers. write some damn code

Thank you for your interest in our paper. Even if negative, it makes people think.
I think we addressed your point on writing some code in our post (“You should produce a better model than existing ones”).
There is theory and there are models. They are not equivalent. Theory comes first.
What does it mean in our case? We present a theoretical estimate of circulation power that fits the observations. Such an estimate does not exist in the meteorological theory on which the current models have been built. So where the current models are just fitted to reality (because of lacking theory), we offer a testable quantitative framework. And this is not about some detail — it is about a key parameter of atmospheric circulation: its power.
This is at least interesting, as admitted by even most critical peers (see, e.g., p. C14689) in the review of Dr. Held. At most it means a re-appraisal of our understanding of how the atmosphere works. So I see no harm if our work receives some attention.

“unconfirmed, likely wrong, inconsequential physics” was it Steven? Then why did the Knights of Consensus, Joel Shore, Nick Stokes, Eli Rabett and Jim_D all charge into the melee back in 2010? Surly if the paper was “inconsequential” that wouldn’t be required. The paper wasn’t inconsequential. Anastasia had accidentally got too close to exposing the big lie of AGW.

All it would take for the Makarieva Effect to work, would be for a rising moist air mass to be more diabatic than a dry air mass. And of course it would be as it is saturated with the most important radiative gas in our atmosphere, H2O. But if radiative gases could have some role in horizontal air circulation, what would be the consequences for vertical circulation? Further investigation would reveal that radiative gases are critical to all vertical convective circulation below the tropopause. Without this our atmosphere heats.

To keep pushing a failed hypothesis as fact years after you knew it was wrong is rancid behaviour. Trashing science in another discipline to defend the “Cause”? Simply putrescent.

I would vote for wrong rather than inconsequential because a loss of vapor without latent heat release would result in an increase in density and loss of buoyancy as dry air filled in to replace the lost vapor and equalize the pressure (dry air is denser than vapor). The key process for buoyancy generation is the latent heat.

Anastasia. you did not address my point about writing code.
1. you will address this point when you do IN FACT write some code.
That is ‘addressing’ the argument.
2. You couldnt explain the math well enough for a third party to code, see Nick stokes comments.

Merely writing words that come after mine does not constitute addressing the issue. your equations were not clear enough for third parties to understand ( so nobody could code up your stuff for you ) and you refuse to do the work yourself. You have not addressed the issue. Write some code and you will. This isnt addressed my writing more words its addressed by writing more clear math or your own code

Steven, ” your equations were not clear enough for third parties to understand ( so nobody could code up your stuff for you ) and you refuse to do the work yourself. ”

I do not think that we deserve this reprimand. In our ACPD paper (2010) we introduced a new physical concept. No code at this time, just discussing basic physical ideas and demonstrating their potential significance.

Now then we took this concept, wrote the full system of equations and solved them for two particular problems: hurricanes (where vertical velocity can be neglected) and tornadoes (where vertical velocities are essential and cannot be ignored). Unlike in the existing hurricane models, we did not use any a priori fitted parameters to match the observations. But in both cases we obtained meaningful results.

We have been doing some relevant additional research as well. We remain hopeful that there are interested researchers who will join us in developing this topic. It might be a matter of time.

So, of course, if you command “write the code” and I do not, this can be interpreted that I have not addressed your comment. But my point simply was that “writing the code” and obtaining a meaningful scientific result is not the same. The latter can sometimes go without the former.

Steven Mosher
This is a discussion about basic science. We have never demanded you or anyone to put this in a GCM (so the reaction seems strong). The arguments included above explain why we don’t want to do it either. Even if we felt able (and I for one certainly dont) that is not our interest at this point. We have aken considerable efforts to show why this is a powerful mechanism and hope that it will be evaluated. If you cannot follow our derivations and logic this discussion is an opportunity for us to clarify.

The controversy is not about the immediate local consequences of condensation or about any other issue of such basics, it’s about the claim that you present a previously disregarded mechanism for driving winds. For that you should present analysis that’s relevant and strong on this level. That may well require rather extensive use of atmospheric models. It’s your duty to do that if you wish to be taken seriously.

Pekka Pirilä
Rmember we are offering a theory to be evaluated. We are not claiming final proof. Its an important difference. The model idea is one I really dont get at all.
In any case I think we do what you are asking already. We characterise the pressure forming process in analytical form and then show that it has sufficient power to drive global atmospheric circulation. (All without models).
Non-transparent models do not and cannot offer strong evidence (read the blog above). Real world data do. Evidence is building up too (see http://www.biotic-regulation.pl.ru/index.html). e.g. There are various estimates for hurricane systems all based on simple analytically defined physics that match with observations. There are also empirical matches with forest cover rain and seasonality. I dont know if you have looked at all those.

You may be offering something to be evaluated, but you should not expect that it will be evaluated in any depth until you can give good enough reasons for others to do that.

People have all kind of ideas and theories. A very small minority of them will ever be evaluated in depth by scientists. In most cases that’s the correct fate for those theories. The very few exceptions must be introduced well enough for getting past the first hurdle. It seems that you haven’t fully succeeded in that even though you got published. So far my feeling is that this is the right fate for your ideas.

Pekka Pirilä
One last shot (late here):
Maybe it is easier to look at this in terms of specifics. We indeed address an effect which Dr Held noted has been “traditionally considered to be small”. We provide the first detailed analytical account of this effect and find that it is not small but capable of doing significant work by accelerating air masses.
In section 4.3 in our paper: “Regarding previous oversight of the effect” we consider and explain how the idea that it was small can be explained if it actually isn’t.
Our demonstration of it being big enough to care about comes from showing that the power of this effect over the world is sufficient to generate atmospheric circulation. It’s a rough estimate but it is a good one — if it was “small” it wouldn’t work (its also the first time such an analysis from first principles has been offered … your models cannot do that). There are other estimates from some of my co-authors showing similar success with certain aspects of hurricanes. So, now, why is this all so minor for you? These all sound interesting – right? If not what’s wrong?

The effect, if correct, is inconsequential. The way for you to respond to this objection is to actually do some work or write in such a way that others can do the work. You’ve done neither. So,don’t assume that you have addressed the concern when you have not. Its pretty easy. Just say
“we refuse to do the work necessary to incorporate this into a GCM and we refuse to describe what we think in such a way that others could implement it”

I’ll return, for example, to the comments made by Nick:

“But your justification was based on molecular kinetics, and you incorporated it in a continuum equation. Now you seem to be saying that, if that’s wrong, it’s still true on some larger averaged scale. But what is the justification for that? And how can an averaged result be incorporated in differential equation maths?”

Simple question; How can an averaged result be incorporated in differential equation maths?

Mosher everybody participating in the scietific endeavour realises that there are limits to every study. It’s common for critics to demand more and more evidence to support work. But it’s mistaken. These authors have what they have and are putting it out for consideration. The common refrain is “beyond the scope of this study” and the authors have adequately expressed that. Stop pestering them for something you know they cant provide.

Not really. Water, water vapor and ice are the source of the majority of the heat capacity that regulates heat flux. The effect may be small compared to an over estimated “average” radiant impact, but 0.8% is significant compared to 1%, which is about the “negative” latent feed back at the “true” surface.

Leaving aside the question of who, ultimately, is correct, I have to say that, from this layman’s perspective, at least, you’re coming off as completely bent. Your insistence that the first stage of a challenge to the GCMs should be to re-write them is just insane. David’s observation that the current models were built up by thousands of people, over years, if not decades, seems to me to dispatch that suggestion, all by itself. Obviously, re-writing will require a concerted effort of numerous people, and, therefore, long before that re-writing begins, a process of devloping a concensus to do so is a prerequisite. And this disussion seems, clearly enough, the first step of a the process for developing that concensus.

This process has already cast light on degree to which the models are built on fudge-factors and false assumptions, and I’m already greatful for that enlightenment. The way they’re held up as “proof” of the concensus model seems particularly threadbare to me, now.

Steven Mosher “The way for you to respond to this objection is to actually do some work or write in such a way that others can do the work”

Thanks for the suggestions.

Note that all the authors but myself are working in a foreign language. We have sought to publish in a discipline with conventions very different than our-own. Now we have taken all the steps needed to publish our ideas in your language in your discipline in your journals and we have stopped by to discuss it with you. We do that because we think you might be interested (isn’t that why you are here?). But now you want us to build your models too. Demanding us to do it all ourselves seems a little like CERN engineers demanding the particle theorists should shut up about their theories until they have made their own colliders.

I’ll speak personally: what motivates me at this point is the question whether these theories are true and what it means in terms of land-cover and rainfall reliability for millions of people around the world. GCMS don’t help (they will not clarify the truth of the physics or be accurate enough any time soon to define concerns). So I have other priorities. If someone else wants to do it I can acknowledge value in the GCM model option. I do see why climate scientists need to do simulations to test ideas — but it cannot provide the kinds of proof that I find convincing (epicycles were long considered the best way to forecast planetary motion).

So, what would I hope for with your GCMs? I would hope we find GCM people with skills and interests who wants to do it, have the time to invest and, if the equations are a problem, can ask guidance. Doesn’t sound too hard. Lots of science is collaborative these days.. Let’s hope that I’m right.

You do sound like you have tried to follow our paper which I do appreciate — if you wanted to try and model the ideas yourself I believe that help would be available.

I agree with the basic premise that condensation does involve an effect on atmospheric pressure but that is simply a mirror image of the effect of evaporation lower down.

The question seems to be whether there really is something new in this that is not already implicit in the known workings of the water cycle and adiabatic ascent and descent within the main high and low pressure cells that together form our permanent climate zones.

It is clear that the water cycle enhances the adiabatic movements within an atmosphere and perhaps this is the first attempt to quantify and explain that enhancment in detail.

Certainly potential energy is at the heart of the matter and latent heat is indeed a form of potential energy so this could well be consistent with my own ideas regarding the water cycle as a regulating factor.

Whether it is a complete answer to the question as to how the atmosphere might stay at the same temperature despite variable radiative characteristics of constituent gases may be doubtful (I think it is primarily a pressure based process involving adjustments in atmospheric volume) but it may well be a useful step forward in explaining how the parts of the system fit together.

It is my understanding that radiative gases provide an additional radiative route for energy loss to space that non radiative gases fail to provide.

Thus with GHGs in an atmosphere the circulation can slow down because more of its job of maintaining top of atmosphere energy balance is done for it by those radiative gases.

The Makarieva paper makes an attempt to quantify the extent to which the water cycle and the phase changes of water could further enhance system stability by accelerating (or indeed decelerating) energy loss upward in response to more (or less) GHGs in an atmosphere.

“with GHGs in an atmosphere the circulation can slow down”
On the contrary, without radiation to space from the upper troposphere atmospheric convection would stagnate. In this great heat engine, the major heat input is at the earth’s surface and lower troposphere, the “boiler’ so to speak. The upper troposphere is correspondingly the “condenser”. There have been many “heated” discussions on various blogs as to the hypothetical structure of the atmosphere composed of no greenhouse gases, only non radiative gases.

Can anyone please explain for me (i.e. in simple, non-technical terms) the significance of this paper to the estimates of climate sensitivity that come from the models?

Does it mean that, if this new physics were incorporated in the models, the models would say climate sensitivity is higher or lower than what they are currently saying?

Please explain why (higher or lower)?

Could this close the gap between the climate sensitivity estimated by models and climate sensitivity estimated from empirical evidence (as in the draft IPCC AR5, WG1, or perhaps even down to what Nic Lewis is suggesting)?

The ‘sensitivity’ is defined as the average of multi-model ensembles. Each of the members of the ensemble is a non-unique solution of a set of nonlinear equations. The ‘member’ is selected on the basis of ‘a posteriori’ solution behaviour. It looks plausible so it is in. So sensitivity is based on what seems plausible – think of a number – and not an any unique, deterministic solution to an equation.

Sound mad I know – which is why I persist in quoting people like James McWilliams and Tim Palmer.

‘Atmospheric and oceanic computational simulation models often successfully depict chaotic space–time patterns, flow phenomena, dynamical balances, and equilibrium distributions that mimic nature. This success is accomplished through necessary but nonunique choices for discrete algorithms, parameterizations, and coupled contributing processes that introduce structural instability into the model. Therefore, we should expect a degree of irreducible imprecision in quantitative correspondences with nature, even with plausibly formulated models and careful calibration (tuning) to several empirical measures. Where precision is an issue (e.g., in a climate forecast), only simulation ensembles made across systematically designed model families allow an estimate of the level of relevant irreducible imprecision…

In each of these model–ensemble comparison studies, there are important but difficult questions: How well selected are the models for their plausibility? How much of the ensemble spread is reducible by further model improvements? How well can the spread can be explained by analysis of model differences? How much is irreducible imprecision in an AOS?

Simplistically, despite the opportunistic assemblage of the various AOS model ensembles, we can view the spreads in their results as upper bounds on their irreducible imprecision. Optimistically, we might think this upper bound is a substantial overestimate because AOS models are evolving and improving. Pessimistically, we can worry that the ensembles contain insufficient samples of possible plausible models, so the spreads may underestimate the true level of irreducible imprecision (cf., ref. 23). Realistically, we do not yet know how to make this assessment with confidence.’ http://www.pnas.org/content/104/21/8709.full

Any change in a model can produce divergent solutions that are not predictable beforehand – it is the nature of the nonlinear Navier-Stokes equations.

‘Lorenz was able to show that even for a simple set of nonlinear equations (1.1), the evolution of the solution could be changed by minute perturbations to the initial conditions, in other words, beyond a certain forecast lead time, there is no longer a single, deterministic solution and hence all forecasts must be treated as probabilistic. The fractionally dimensioned space occupied by the trajectories of the solutions of these nonlinear equations became known as the Lorenz attractor (figure 1), which suggests that nonlinear systems, such as the atmosphere, may exhibit regime-like structures that are, although fully deterministic, subject to abrupt and seemingly random change.’ http://rsta.royalsocietypublishing.org/content/369/1956/4751.full

We are not at the stage of having ‘systematically designed model families’ – thus the first hurdle for precision is not cleared. Solutions are literally chosen subjectively from many possible solutions and the range of possible solutions remains unknown.

I have said this many times in many different ways – but the understanding of dynamical complexity remains elusive. These models are most certainly chaotic in the sense of theoretical physics as shown by Lorenz in the early 1960’s.

This work suggests to me that the warming effect of rising CO2 is much stronger than previously thought. If warming results in enhanced winds that draw heat from the surface high into the atmosphere then the surface will need to warm more in order to achieve equilibrium.

I would urge climate scientists to test this mechanism, among others, in their GCM models so they can find out exactly how much higher climate sensitivity would be.

Modern Science Ideas,
Climate sensitivity is a hypothesis and concept only resulting from the greenhouse gas effect hypothesis. We went by this hypothesis because we had no data back in the 1830’s. We are in 2013 and have solid data to develop theories and laws of the climate and we should not settle for a hypothesis, particularly on a subject that can greatly affect our llivelihood. I think we should start looking seriously at papers similar to this one.

“Poe’s law, named after its author Nathan Poe, is an Internet adage reflecting the idea that without a clear indication of the author’s intent, it is difficult or impossible to tell the difference between sincere extremism and an exaggerated parody of extremism.”

Consider the profile of a typical humid atmosphere. As we rise in the profile, both pressure and temperature fall, eventually the water condenses and two things happen: the condensing water releases its latent heat and pressure drops because codensed water has far less volume than the gas it replaced.Dynamically we now have a new situation. We are in the micro climate of a cloud. The latent heat released will tend to reheat the gases in the cloud and this can create an unstable situation. That it does create an unstable situation is evident because clouds continue to exist. Clouds are nothing but condensed water vapour..The latent heats of evaporation and condensation are the same, so this situation can continue so long as there is a supply of humid air from below, the cloud will grow, or shrink if the supply reduces.

If you accept the above theory then the ‘new’ theory certainly applies in the lower troposphere, but breaks down at the cloud level.

The heating that occurs from condensation reduces the environmental lapse rate. When the environmental lapse rate is smaller than the dry adiabatic lapse rate the atomosphere is conditonally unstable and some weather event is a likely consequence in the restoration to stability.

Do you know the spectrum of the photons emitted when gaseous water undergoes the phase transition?
Do you know the absorption/light scattering properties of gaseous and solid water in the low pressure atmosphere?

Thank you, DocNartyn, for your reply.
Yes, the phase transitions result in both enission and absorption of photons as kinetic energy, for water. For a stable cloud they would be about equal. No, I don’t know the spectrum other than it is IR..Yes, water is a so-called greenhouse gas absorbing IR, around 40% of the planet’s radiatiion. For climate implications see my website above..

In the past I have read commenters saying things like:
“Coastal winds are driven more by temperature differences between land and ocean.”
“Hadley cells are driven by temperature differentials between the equator and higher latitudes.”
So, is that so?

Here is an small exaggerated example:

I have two horizontally adjacent parcels if air, both with an identical specific gas constant, R.

Parcel one has a pressure of 10,000 Pa and a density of 1 kg/m³.

Parcel two has a pressure of 20,000 Pa and a density of 2 kg/m³.

Which way doth the wind blow between the two parcels?

( For those that may not realize the relationship being addressed, both parcels have identical temperatures by the ideal gas law of P/ρ = R·T )

Some would say no wind will blow at all, they have equal temperatures. But I tend to think they are simply viewing a one-dimensional vertical-world but applying that concept horizontally. With gravity involved, this is true vertically in a planetary atmosphere, no vertical wind would exist. The density, ρ, will track the pressure, P, without an energy density differential between the two. Seems this does not apply when viewing the same example horizontally.

Perhaps some of the scientists and engineers here may help me shed some light on this curious question, I think it is critical in this substance of this paper.

I tend to think the wind blows from parcel two to parcel one because of both the higher pressure and the higher density of parcel two.

I might also add that you can easily think of a crossed example of two parcels with different temperatures but identical pressures, then the densities are different.

Also, there is an example with two parcels with different temperatures and pressures but the densities are identical.

Which takes the precedence when looking at the horizontal wind, the pressure difference, the density difference, or always the temperature difference?

I would say pressure is always the ruling factor in all cases.

There may be a tendency for temperature to follow the pressure but also, because of the densities, this may cause this rule-of-thumb to fail. Can any physicist or meteorologist out there either agree or disagree with that? Just trying to firm my understanding in these areas.

A Google search for the phrase “exact and inexact differentials” finds many thousands of explanations, in both articles and books, of this subtle (yet crucial) thermodynamical distinction.

And so it is concerning that, beginning with equation (1)

Makarieva et al. have (inexplicably) adopted a notation that fails to make this crucial distinction.

Concern increases further when these authors ignore the vast engineering literature on the flow of steam (which is precisely the domain where the effects they are describing are most prominent).

This paper makes extravagant claims, and had a tough time in review. This could be because:

(1) the reviewers are demanding an extraordinarily high standard of evidence and clarity of exposition, before accepting transformative findings, and/or

(2) the paper is obscurely written, with poor notation, and scanty references, and/or

(3) interpreted literally, the physics is just plain wrong, but the author’s notation is so poor that they themselves do not realize it, and/or

(4) once minor notational infelicities are corrected, the authors have found a novel path to rederive well-accepted thermodynamical models.

Conclusion On the evidence, it is entirely plausible that (1,2,3,4) all are correct! And that is why (quite properly) much further work will be required of the authors, along with independent derivation of their results by other workers using different methods, before these ideas are accepted — if indeed these ideas are not old wine poured into a new (bad-notation) bottle, or alternatively, just plain wrong.

Thanks anyway! Didn’t see your reply before posting I’d found it already. I skimmed it last year and didn’t think the effect would change the price of tea in China, so to speak, and didn’t spend any more time with it as a consequence. Not feeling any different about it now either.

The stuff you cited on “biotic regulation of climate” is interesting (I wouldn’t call it “wacky”).

The hypothesis that the biota exerts a real and significant regulating effect on our climate sounds reasonable, even if it’s not corroborated by any empirical evidence.

Where the paper gets into trouble is toward the end. Let’s go through the last paragraphs:

As the humans disintegrate the natural ecological communities in the course of civilisation development, the stabilising regulatory mechanism of the natural biota becomes less and less efficient.

(Unsubstantiated. Physical evidence for this claim?)

Currently this is manifested in the growing frequency of extreme climatic events like floods, draughts, hurricanes, tornadoes etc.

(Purely conjectural. There is no physical evidence to support this suggestion, which even IPCC is beginning to back away from.)

However, if the threshold of anthropogenic disturbance of the natural ecosystems is passed, this may switch the climate to either of the two physically stable states that are life-incompatible.

(Purely conjectural. This is based, among other assumptions, on an unsubstantiated premise above on human-induced extreme weather.)

Given this, it is remarkable that the climate stability phenomena receive so little attention within the modern scientific community, theoretical biologists included. The biological theory just accepts like axioms statements that, if re-evaluated, may completely undermine its current theoretical foundations.

(Too much uncertainty regarding the existence and magnitude of “biotic regulation” of our climate and the purported negative human impact on this mechanism; no mention of possible positive effect on biota of higher CO2 concentrations and/or slightly warmer temperatures.)

They are saying that the loss of water vapor reduces the pressure and effectively sucks the air up regardless of buoyancy. This does not account for the environmental temperature and how stable the atmosphere is to convection. According to their theory, this pressure gradient operates just as strongly in any conditions. What really happens is that the latent heat release warms the ascending air which only rises conditionally on the warming being strong enough to keep the lifted air buoyant relative to the environment. Convective instability is about the best known and validated process in meteorology. Weather forecasters rely on being able to tell whether a temperature profile supports deep convection.

Jim, thank you for your persistent interest.
“Convective instability is about the best known and validated process in meteorology. ”
Had it been the case, there would have been no problems in accounting for moist dynamics in current models. But the problems are very serious precisely with reproducing the observed circulation intensity in the moist atmosphere (be that, for example, hurricanes or monsoons).

But I agree that it is certainly the best known theoretical concept. It was introduced when there were no models and no program code, and still is believed to have merit. We, on the other hand, offer another one and argue that this new one is more important.

“What really happens is that the latent heat release warms the ascending air which only rises conditionally on the warming being strong enough to keep the lifted air buoyant relative to the environment.”
This is only half of the story. In simple words, in order to lift a moist air parcel, you must draw a dry air parcel down: this is what circulation is about. Since the air descends dry adiabatically and becomes warmer than the surroundings, there is an upward force acting on it that prevents the descent. The potential energy associated with the positive buoyancy of your rising parcel must be enough to allow the warm dry air parcel to descend. When you calculate what is left to generate kinetic energy, you will find that under most conditions the two processes basically cancel each other, so their overall impact on dynamics is negligibly small. Basically, it is a well-known point for many years.

For our effect there is no such compensating process in the descending branch of the circulation.

The ideas of convective instability are founded on basic thermodynamics and don’t need models to prove them. If your theory can distinguish convective stability from convective instability, I would be very surprised, but even then, it will only be matching the old theory that works already. For air to rise, it only has to be warmer than its surroundings, which is how thermals work. Clouds are like thermals but are assisted by latent heat release. This is all very well explained already and needs no new theory because there are no gaps in the understanding. If you think there is an unexplained phenomenon, your paper has done a poor job of describing what that is exactly, because there is no point of a new theory unless there is something unexplained by current theories.

“For air to rise, it only has to be warmer than its surroundings, which is how thermals work.”
This is only true for dry air and demands the existence of an external horizontal temperature gradient. As you know, in hurricanes for example such a gradient is absent.

So, let us keep focused on moist processes. For a moist adiabatic ascent, it is not enough that the rising air parcel is warmer than the surroundings. It is also necessary that the descending air parcel is cooler. Meanwhile as the descent occurs dry adiabatically, the dry air parcel tends to be warmer too. The net result is that the degree to which “clouds are assisted by latent heat release” is on average negligible.

Jim “because there is no point of a new theory unless there is something unexplained by current theories.”
As we clarify both in the paper and in the post, current theories do not provide a quantitative estimate of circulation power. Our new theory does.

Anastassia, your concept of buoyancy is not correct. Hurricanes only work because the rising air is warmer than the environment, even if only one or two degrees. The environment does not have to descend much because there is more of it, so a small descent by a large area compensates a large ascent in a small area (updraft core).

Jim, “The environment does not have to descend much because there is more of it, so a small descent by a large area compensates a large ascent in a small area (updraft core).”
These are all ideas that are plausible at the first sight but, as we emphasized in the paper and the post, lacking a theoretical proof. When the descent occurs on a large area, however small the local work against positive buoyancy of the descending air parcel, total energy expenditure will be comparable with potential energy released in the updraft because of being integrated over a large area.

My sense is that many of the commenters cannot quite get their arms around your concepts..wacky stuff is one characterization. I kind of like the fact that you are challenging conventional thinking,. Many in the scientific community nearly 100 years ago thought Einstein’s ideas were wacky as well. Keep pushing the envelope.

Thermals over the ocean are next to nil. There’s very little difference between SST and the surface air temperature. On average it’s less than 1C. Over dry land the difference can easily be 40C. High winds happen in the dryest of environments and are driven by thermal convection but over the ocean it’s all about water vapor which ascends because it’s lighter than air not because it is warmer. Condensation at altitude then causes a pressure drop which is by far the most significant driver of vertical motion – bouyancy (over the ocean) is like the starter motor which sets the main engine in motion. Over dry land there is no main engine only the starter motor but that starter motor can be surprisingly powerful because the temperature differential between ground surface and air in contact with the ground can become very large under a hot sun. Over the ocean you could have the sun as close as it is to Mercury and it won’t make the water much warmer than the air so long as there’s water available to evaporate.

“Since the air descends dry adiabatically and becomes warmer than the surroundings,”
Air temperature can be equal to that of surroundings at best. Otherwise you would be creating energy, and this is impossible.

Jim DFor air to rise, it only has to be warmer than its surroundings, which is how thermals work.
incomplete understanding, as a soaring pilot I have spent 1,000s of hours observing thermals from inside them, it is not common but neither is it unusual to find the mean temperature of the air in a thermal remain at or lower than the surrounding airmass at all altitudes from source through to top of convection.

Of course lapse rate is the driver of airmass stability but some thermals obtain their buoyancy due to higher water vapour content, usually caused by strong insolation causing evaporation over saturated ground resulting in localised higher levels of WV at thermal source.

I am certain of only one thing in life, there is far too much certainty

“We have described a new and significant source of potential energy governing atmospheric motion. Previously, the only such recognised energy source was the buoyancy associated with temperature gradients.”

OMG. Is this piece of 19th century physics new in this field? Gravity is a weak force, molecular forces are strong.

Moving water into the gas phase, 1 micron away from the surface of droplets (evaporation) needs the same amount of work required to lift it to a height of 230 km above Earth’s surface. In case of ice crystals (sublimation) it is 264 km. These values are more than an order of magnitude higher, than tropospheric thickness, therefore potential energy storage in the atmosphere is dominated by the water cycle.

Also, mass of water evaporated (and recondensed) annually is roughly the same as that of the entire atmosphere. Most of it (~90%) never reaches the surface, but re-evaporates in mid air. Atmospheric distribution of water is extremely non-uniform on all scales.

Back of envelope calculations are of huge importance. They are the first step in separating the wheat from the chaff. In engineering and computer science, in my experience, these are referred to as “sanity checks” i.e. we do some very rough calculations that tell us if there are any fundamental errors leading to physically impossible (insane) consequences. If whatever it is passes the sanity checks then we can get down to the more detailed analysis looking for more subtle flaws.

The vertical exchange of a less buoyant parcel above with a more buoyant parcel below is the source of kinetic energy in thermals. It comes from potential energy. The same happens with convection when conditional instability is considered because moist air releases latent heat and effectively becomes warmer than the dry air it replaces it higher levels. The dry air has no problem descending when warm thermals rise through it. The paradox would be if the potential energy somehow couldn’t be released. It is an unstable situation, like standing a pencil on its point.

There’s a good measure for determining the importance of their addition. It’s given by the ratio of pV to latent heat of condensation. Both are in units of energy. p is the total pressure at the point considered and V is the volume of the condensing vapor. This ratio is small in all cases in the atmosphere.

Nick Stokes | February 1, 2013 at 1:08 am |
“It was point five in my first discussion entry. It’s still here, and emphasised; the equation is S = CNv.
Now physically this is nonsense. There’s always some humidity, but it mostly isn’t raining. Condensation doesn’t occur at all until Nv nears saturation. ”
Thank you for your comment.

The problem that has to be addressed here is the problem of spatial scale. Formally, condensation rate S enters the differential equation but we know that in the real atmosphere we are always talking about some macroscopic scale. E.g. the one determined by the spatial resolution of the model.

If the considered scale harbors the circulation cell as a whole (i.e. both the descending and the ascending branch), then S and Nv characterize the mean condensation rate in the considered cell. So despite the mean Nv is unsaturated, the mean condensation rate is not zero.

Accordingly, in our estimate of the global circulation power we use global mean precipitation P which characterizes both regions where the air is ascending and precipitation is high and regions where the air descends and precipitation is low.

If we take a closer look on the circulation differentiating the areas where water vapor is saturated and where it is not, we will need to consider that the condensation-induced pressure gradient spreads outside the condensation area to drive the circulation as a whole. Eq. (4) in our post becomes generally valid in its integral form (when both parts are integrated over volume V occupied by the circulation), while its local form is somewhat modified.

Please note also that to observationally verify Eq. (3) in our post (which contains the basic physics) you do not need to know anything about condensation rate at all.

But your justification was based on molecular kinetics, and you incorporated it in a continuum equation. Now you seem to be saying that, if that’s wrong, it’s still true on some larger averaged scale. But what is the justification for that? And how can an averaged result be incorporated in differential equation maths?

Pekka Pirilä | February 1, 2013 at 2:50 am |
“There’s is no reason for the very small loss of gas would create significant pressure effects. The little it does goes against the much stronger effect through the influence on temperature. ”
This is a qualitative statement which lacks a proof. If there existed a theoretical estimate of global circulation power based on “the influence of temperature” we could compare it with ours and decide. But such an estimate does not exist leaving the field open for theoretical research.

“The claim that vertical movements of gas could not compensate the changes from loss of gas molecules lacks all justification. The whole phenomenon is related to vertical movement of gas and changes that very little. There’s nothing that would make that difficult and require some strong winds.”
The point is there is continuity equation, and when the gas goes upward, it disappears from below. Thus re-establishment of hydrostatic equilibrium in the area of condensation leads to the appearance of a pressure drop at the surface. Such that there is now a pressure difference between the condensation area and the surroundings. It drives the wind.

But then it must be noticed that water can disappear higher up only when it’s first introduced at the surface. This circulation of water is to a large extent local and occurs in one rising column. The volume of gas in that volume is increased by a couple of percent (or less depending on temperatures), but that does not influence much what happens elsewhere and that does not influence much the horizontal pressure gradients.

I looked at all the messages written while I was sleeping only after writing my above comment and another comment higher up. This reading brought up that similar points have been made by many others.

The principal conclusion is that the paper does not present any coherent view of the issues. It’s incomplete and leaves most of the essential issues untouched. Therefore it’s not immediately obvious from the paper, how badly it’s wrong. Reaching this conclusion requires that the rest of the physics is taken into account. What’s discussed in the paper is just a small detail that has a totally different and far less important role when put in the connection with the rest.

A detailed and very accurate calculation of the atmospheric flows of moist air must take into account also the effects related to the volume taken by water vapor both when water vapor is added by evaporation and when it’s removed in condensation, but these effects are very minor corrections and not a source of anything significant.

“A detailed and very accurate calculation of the atmospheric flows of moist air must take into account also the effects related to the volume taken by water vapor both when water vapor is added by evaporation and when it’s removed in condensation”

I agree. At this point we say: “it is significant, we have a theoretical estimate and it agrees with observations.”

You say
“but these effects are very minor corrections and not a source of anything significant.”
I think that if you could provide some specific justification for this statement, it could move the discussion forward. But certainly your opinion statement is valuable per se.

I have only the intuition and experience of a physicist in judging what factors are important to include in a calculation.

Here the main reasons for the conclusion is that the case is an uplift of most air (that’s the only place where your effect is present). The whole process is formed from the heating and evaporation at the surface and from the uplift convection where the condensation occurs. The vertical motion is essentially unrestricted for that case and controlled fully by the density of the air at various altitudes and by the energy available at the bottom to heat the air and to drive evaporation.

Heating and adding water reduces the density at the bottom. That leads to the uplift. Air from some side must flow in to maintain the pressure at the bottom. The amount of water in the uplift reduces the flow from the side because it adds to the volume and because evaporation takes most of the energy available reducing the overall flow of air.

Higher up the water starts to condensate. That adds sensible heat to air and reduces the temperature drop by altitude (moves from dry adiabat to moist adiabat). The gradual condensation affects also the density increasing the density of the other gases in the remaining air.

The above changes mean that the volume of flow is reduced where partial pressure of water vapor is low and is a little larger than that where we have more water vapor.

if you wish to say anything of what’s going to happen you must describe fully all the above main phenomena. Only then can you start to conclude anything on the influence on winds. Based on what I write above the effect on winds is almost certainly small and may actually reduce them rather than add to them,

In short: Solve first the vertical flows fully. Then you can look at what happens horizontally.

Pekka PiriläI have only the intuition and experience of a physicist in judging what factors are important to include in a calculation.

How can you tell that, in this case, the effect is too small to be significant? Compared to the gross flows of energy through the system, radiative and non-radiative transfer, it is a small effect. It also is not, as you say, closely related to the “overall picture”. However, the hypothetical effect of doubling CO2 is also a small effect compared to the gross energy flows, and the only tie-in with the “overall picture” is the hypothetical equilibrium effect.

Unless you have a stronger and more detailed analysis than what you have presented so far, your judgment that the effect is insignificant is premature. I think you (or someone) would have to show that their effect is not “there” (a word you used previously), or that they have overestimated it by an order of magnitude. If the effect is “there”, then it is deserving of an accurate estimate. This paper is a first attempt.

I have only the intuition and experience of a physicist in judging what factors are important to include in a calculation.

Thank you for taking time to explain your view. Let me explain mine at the same qualitative level.

First, in your view what happens when moist air ascends, you have not considered the effect we are talking about. When an air parcel occasionally moves upward, its pressure changes as prescribed by the ambient conditions (e.g. of hydrostatic equilibrium). But water vapor due to condensation behaves differently and its vertical pressure change deviates significantly from that of the other gases. This creates a non-equilibrium pressure gradient that does work on the gas. We quantify this work and show it is significant.

Second, the effects of changing density and latent heat release in the process that you describe (of a one-dimensional ascent of a moist air parcel) are well-known and discussed in Section 3.4 in our paper “Comparing forces due to condensation and buoyancy”. Such considerations do not say anything however about the real world pressure gradients and the real potential energy associated with latent heat release.
This is because in the real world when the lapse rate is not dry adiabatic (and it is not dry adiabatic in an environment where condensation is at least distantly present), the descending air experiences an upward force being drier than the surroundings. This force apparently suppresses the circulation and must be suppressed by an equivalent force acting in the uplift. The net effect (the work of both forces) can be close to zero. This descending branch is, in a way, a “burden” on any circulation planning to rely on latent heat.

So despite seemingly huge amounts of latent heat, its dynamic effect can be negligible. Inferences drawn from consideration a one-dimensional vertical flow are, in this case, misleading.

I’m with Curry and question the magnitude of the effect but not its existence. Condensing water vapor causes a pressure change which in turn produces kinetic energy. The power stroke of early steam engines were driven in this manner – a piston rises drawing in low pressure steam then the cylinder is cooled causing the steam to condense and a negative pressure then pulls the cylinder down. The cylinder is connected to a rocker arm the other side of which is attached to a water pump pulling water out of mine shaft so mining can continue. That’s pretty much the first commercial steam engine. The negative pressure can approach ambient air pressure (~14.7psi at sea level) although in operation the cylinder wall stays pretty warm which reduces considerably the pressure differential. On a very large piston a few psi adds up to a lot of power. Those first steam engine pistons were hundreds of square inches. A source of cold water, which after startup could be the evacuated mine water, was required to cool the cylinder for the power stroke.

Now then, it’s nowhere near a new idea that the same thing happens in the atmosphere only the power produced by condensation is pumping air horizontally in the atmosphere instead of moving water out of a mine shaft. In light of that I have to echo Pirila’s comment about not knowing exactly what this adds to current knowledge.

I’d also dispute the author’s position saying thermals expend all their energy in vertical motion with none left over for horizontal displacement. Strong horizontal winds exist in the very driest of environments (consider the Antarctic interior) which seems to be a simple proof that thermal updrafts do indeed generate horizontal displacement in surrounding air masses.

“I’d also dispute the author’s position saying thermals expend all their energy in vertical motion with none left over for horizontal displacement. Strong horizontal winds exist in the very driest of environments (consider the Antarctic interior) which seems to be a simple proof that thermal updrafts do indeed generate horizontal displacement in surrounding air masses.”

Thank you for your comments. Note that I did not discuss dry thermals. I discussed convection based on latent heat release. There is a difference. In dry thermals the lapse rate of the ascending and descending parcel is the same. So if the ascending parcel has a positive buoyancy (being warmer), then the associated potential energy can be available to drive the descending parcel down. The descending parcel following dry adiabat does not experience any upward force hindering its motion.

When there is latent heat the situation is different. The ascending and descending air parcels have different lapse rates. If there is a mean rate of 6.5 K/km, the parcel that ascends moist adiabatically will be warmer than the environment. But so will be the parcel that descends dry adiabatically. It will experience an upward force that can suppress the circulation.

Congratulations to Anastassia Makarieva, Victor Gorshkov, Douglas Sheil, Antonio Nobre, Larry Li and to the editor and executive committee of Atmospheric Chemistry and Physics for successfully getting new information past the gatekeepers of knowledge by saying:

“the handling editor (and the executive committee) are not convinced that the new view presented in the controversial paper is wrong.”

What a sad day for science that so much effort was devoted to blocking its publication.

It appears to me that the Makarieva et al. study has caused some excitement – and maybe ruffled some feathers along the way. Thanks for posting it here.

The best indication that it might be a serious challenge to the prevailing consensus paradigm is the strong reaction it appears to have gotten (and is getting here) by the proponents of the consensus.

Leaving aside some frivolous characterizations (“wacky stuff”, “physics is plain wrong”, “the paper is obscurely written”, etc.), or some non-specific criticism (“where’s the code?”, “the paper does not present any coherent view of the issue”, “this is all very well explained already and needs no new theory”, etc.), the most serious challenge has been that the described effects may exist, but may be too minor to be of any real significance.

As I understand it, Makarieva and co-authors have acknowledged that their findings and conclusions are novel and controversial and that, as a result, current GCMs do not take these findings into consideration.

They state that they hope that “these ideas can gain objective assessment from those best placed to assess them”.

This makes perfect sense to me and (IMO) would necessarily include gaining empirical evidence from reproducible experimentation or actual physical observations in our climate system to validate (or falsify) the proposed mechanism, as well as to quantify its effect.

manaker.
The issue isnt how science operates. Scientists will ignore the paper, unless they can make sense of it better in a way that the reviewers could not.
Frankly, if Nick Stokes, Lucia, and Held could not make sense of it, then I don’t think anyone else will waste their time disproving it OR using it.
In short, it cannot be incorporated into other science until the issues are addressed in a SUBSTANTIVE way.
The real issues are.
A) the publishing process, specifically this journal.
B) cranks who latch onto papers they dont understand in the hopes that this paper will bolster their crank ideas.
C) cranks who assert that this paper that is “not wrong” somehow has arguments on accepted science.

But yes, science will operate normally and ignore bad stuff that just happens to get published.

Would you have been happier if they had gone with anonymous alleged reviewers in one of OMICS hundreds of journals? I bet OMICS would have created a journal just to publish this paper, and given them a discounted price. With regards to the BEST paper, you made it clear that the review process don’t mean squat, it’s getting the box checked that matters. Why haven’t you and Nick, rabette, et al just ignored this paper?

“Held could not make sense of it,”
Held cant make sense of Chekroun either,or the importance of the devils staircase in winding maps as he readily admits,others such as Crucifix,understand the heuristics of M13,more readily such as the ability of Biological complex systems to adapt the environment to their liking.

> The best indication that it might be a serious challenge to the prevailing consensus paradigm is the strong reaction it appears to have gotten (and is getting here) by the proponents of the consensus.

In that case, I propose we give Christopher Monckton, 3rd Viscount Monckton of Brenchley a Nobel prize of his choosing.

I think I have worked out why talk of ‘pressure’ has become confusing.

For a planet with a fixed atmospheric mass and a fixed gravitational field there can be no absolute change in total pressure.

All that can happen is that from place to place there can be pressure variations in the horizontal plane relative to the vertical plane.

Thus, considering a single parcel of air of indeterminate initial volume:

i) That parcel of air can be caused to expand relative to adjoining air parcels either by direct input of more solar energy where insolation is uneven (as it always is) or indirectly by the injection of potential energy in the form of latent heat of evaporation carried by water vapour.

Once it expands it pushes against the adjoining parcels so pressure increases in the horizontal plane but pressure in the vertical plane remains the same so the expanded and lighter air parcel moves in the direction of least resistance which is upward.

In the vertical plane viewed from the surface one then has lower pressure because the rising air is less dense and lighter. The higher the column of rising less dense air goes or the faster it rises the lower surface pressure will become in the vertical plane.

At the same time the changed pressure relationship between the vertical and horizontal planes will set up an air flow which serves to bring in new air low down to replace at the surface the air that has risen.

In extreme scenarios there can be tornados or hurricanes.

Note that from a meteorological point of view that is the formation of a low pressure cell because pressure in the vertical plane has dropped in order to relieve the increased pressure in the horizontal plane.

ii) Now let’s look at the other side of the same scenario which is the condensation process that Anastassia is considering.

When condensation occurs that parcel of air shrinks relative to adjoining parcels when it loses its latent heat of evaporation via condensation.

Having shrunk it no longer pushes against adjoining air parcels. Instead it gives way and pressure in the horizontal plane falls. Again, pressure in the vertical plane stays the same so the contracted and heavier air parcel moves in the direction of least resistance which is downward.

In the vertical plane viewed from the surface one then has higher pressure because the falling air is more dense and heavier. The higher the column of descending less dense air or the faster it descends the higher pressure will become in the vertical plane.

An air flow will be set up whereby the descending air replaces the air at the surface that has gone to replenish the nearby rising column and there we have a circulation.

So, in light of that it is potentially misleading to say that condensation causes a reduction in pressure because one assumes that such reduction in pressure has occurred in the vertical plane so as to accelerate convection.

In fact, condensation only results in a pressure reduction in the horizontal plane and the only effect of that lateral pressure change is to complete the downward half of the circulation already provoked by the initial uplift.

Note that I said that the initial uplift could be caused by any provision of more energy at the surface.

That means that the process I have just described is applicable with or without a water cycle. The only effect of a water cycle is to increase the sensitivity of the system as a negative response to surface heating.

The water cycle assists stabilisation of top of atmosphere energy balance and reduces the need for a more vigorous circulation.

The effect of CO2 and other non condensing GHGs is just the same but without the added efficiency provided by phase changes.

All GHGs make it easier and not harder for the global circulation to match energy in with energy out at top of atmosphere.

I admit that my physics is not good enough to appreciate the details of Makarieva
et al, and I have tried to read the comments to augment my understanding; with limited success. But it seems to me that if this paper is right, then the current climate models are wrong; in a fundamental way.

Now the IPCC has set March 2013 as the deadline for new papers to be considered for the AR5; and we have not reached this date. Is this paper one that the authors of the chapter in the AR5 dealing with climate models must ignore, or admit that the output of the models might not be as robust as they had previously believed? And in which case, the certainty expressed on the SPMs needs to be downgraded.

Is this just another case where we have reason to believe that in past reports have exaggerated the certainty with which they have expressed in the SPMs is far greater than the science warrants?

“But your justification was based on molecular kinetics, and you incorporated it in a continuum equation. Now you seem to be saying that, if that’s wrong, it’s still true on some larger averaged scale. But what is the justification for that?”

My brief response is that the justification is the same as for the smaller scale. If S is proportional to Nv where condensation actually occurs it will unlikely become proportional to the square power of Nv (or anything else) on a larger scale.

Now let me put your question in a perspective. The physics of condensation-induced dynamics is summarized by Eqs. (1)-(3) in our post. This physics has been described in detail starting from our first paper in HESS on this topic.

In our ACP paper we investigated how the same effect can be derived (or understood) from, and agrees with, the mass conservation equation. Our physical justification for condensation rate S (34) was that (1) it should only depend on vertical velocity and (2) must have total air (rather than dry air) subtracted as the reference because of the hydrostatic adjustment of air as a whole. These plausible propositions do show (at least to us) that our approach is coherent and makes good sense. One needs to investigate the process from different sides. We did so and were satisfied with the result.

Now when the readers, including yourself, said (much to our surprise) that the grounds on which we wrote S (34) are not convincing, we undertook additional efforts to investigate its form. We additionally clarified in the Appendix that S (34) agrees with the proposition that S is proportional to Nv. This also makes good sense, because condensation is indeed a first-order reaction. If we, say, found that on a macroscopic scale it somehow becomes proportional to the second power of Nv that would be a little alarming.

Note now that S (34) follows directly from (3) and the energy conservation equation (4) in the blog. So you can either derive (4) (Eq. 37 in the paper) from S (34), or you can obtain S (34) from consideration of the potential energy associated with the ascent of condensing vapor as per (4) (cf. expression for condensation force fc on p. 1044).

We consider an interesting finding in the ACP paper (besides the Hadley estimate) the expression showing how S and Sd are related via gamma to determine the horizontal pressure gradient (Eq. 6 in the post).

“My brief response is that the justification is the same as for the smaller scale. If S is proportional to Nv where condensation actually occurs it will unlikely become proportional to the square power of Nv (or anything else) on a larger scale.”
But as I said, the justification on the smaller scale is completely wrong. Precipitation does not occur proportional to humidity. Nothing like it.

This does not support the proposition on a larger scale.

“If S is proportional to Nv where condensation actually occurs”
S (condensation rate) occurs at essentially one value of Nv, saturation. And it does not have a single value at that point. In saturated air you can have anything from mist to a downpour. It depends on what is happening to the latent heat.

Doc,
It’s a statement in the paper. S=C*Nv. It goes into the system of continuum equations. If there are caveats about scale, they should be stated there, and be taken account of in the math reasoning.

But I don’t think it makes sense on any scale. There’s humidity in the desert on a fine warm day. Where do you see the proportional condensation rate?

There’s cpnstant reversal of burden of proof here. What’s the case for S=CNv? It’s there now in a peer-reviewed paper, I suppose. Anything else?

Nick, please correct me if I got you wrong, but do you really want to spread the message here that we put C = const in S=CNv? Why to create this confusion? Please check back in the text on p. 1054, Eq. (A11). It says that S = wkvNv, with C = wkv being constant with respect to Nv only. It does not depend on Nv, that’s all. Let’s recall that even in molecular kinetics if a reaction is first-order with respect to some substance, the proportionality coefficient is not a universal constant, but depends on the other reaction parameters like say temperature or concentration of other substances.

In our case these other parameters are the vertical velocity and the degree of deviation of water vapor pressure from hydrostatic equilibrium. In the unsaturated atmosphere it is zero. Of course this is not formal molecular kinetics, but the value of this result is that the macro-scale pattern, with S being proportional to Nv, is consistent with what we can expect from a micro-scale consideration. BTW for evaporation E that is not first-order in Nv you will never be able to derive anything of similar kind. It is perfectly plausible that micro-scale properties show up at a macro scale. It may or may not be convincing for you, but there is no error here.

So you can argue that “there are no plausible grounds to believe that S = CNv” and I will argue that there are. The point is that the relationship that is obtained from S (34) is empirically testable for anyone to decide on their own. It also has a different but totally coherent physical interpretation as given per Eq. (3) in the blog. I expand on these points below.

Anastassia, Since there is so much confusion, perhaps a simpler analogy might help.

The saturation vapor pressure of air at sea level and 25C is roughly 1 inch of hg (33millibar). If were possible for all of that to be converted to velocity pressure, that would produce a wind speed of roughly 5 kilometers per minute. I that about what y’all are predicting?

Yes, this is the scale of maximum velocities that are to be observed where the turbulent friction is minimal. This is what we predict for hurricanes.
For a large-scale circulation where friction is significant especially at the surface such velocities cannot be observed. Here what we predict is that the rate of generation of kinetic energy by the large-scale pressure gradient u∇p (i.e. local power (work per unit time) of the pressure gradient force) is determined by condensation intensity as given by formula (3) (or (5) if you integrate over z).
This can be empirically tested by either directly observing velocities and pressure gradients or using a more indirect approach and estimating the dissipative power of smaller-scale eddies. Such empirical estimates of circulation power are available in the literature.
Note also that for hurricanes (3) is also valid, so velocity in hurricanes is an additional prediction.

Thank you for your interest. I think that when people appreciate the physics of this effect, many original studies may be designed that we may not foresee right now. One specific thing I’ve been thinking about is that there are some behaviors in the existing numerical models (e.g. of hurricanes) that remain obscure right now, but which can be explained within our approach.

Regarding empirical data, the most straightforward thing is that we give a testable formula for circulation intensity based on precipitation. We have applied it to the mean circulation power and average hurricanes, but it is possible to check it against temporal variations in both regional circulation intensity as well as on individual cyclones. One will need an independent estimate of dynamic hurricane intensity, which can be derived from the observed pressure gradients and radial velocity.

You mention possible ways to get empirical data to either validate or falsify your hypothesis regarding wind intensity based on precipitation.

Are these basic data being gathered today?

I assume that if these measurements show no direct correlation between wind speed and precipitation that this would essentially falsify the hypothesis that this mechanism plays a major role in driving winds.

However, if they demonstrate an repeated direct correlation between precipitation and wind speed, will this be enough in itself to validate your hypothesis, or would additional empirical evidence be required in your opinion?

Thanks for taking the time to answer my questions and lots of luck in being able to move this to the next step.

To accord with modern thermodynamic notation, alter Eq. (1) — and all of the subsequent expressions and conclusions that derive from Eq. (1) — to eliminate references to the (inexact) heat differential , in favor of the (exact) entropy differential .

‘Before discussing the generation of the standard thermodynamic potentials, we briefly summarize the basics of statistical mechanics. We will show how the Legendre transform enters thermodynamics through the Laplace transform of partition functions in statistical mechanics.

Equilibrium statistical mechanics is based on the hypothesis[2] that for an isolated system, every allowed microstate is equally probable. The high probability of finding a particular equilibrium macrostate is due to a predominance of the number of microstates corresponding to that macrostate.’

Quite apart from the number and extent of non-equilibrium processes in the atmosphere and that Earth’s climate is not an isolated system – the paper you reference seems more concerned with the relation of quantum states to macrostates. The concern of the current paper is evidently the macrostates of atmospheric circulation. Please -your vague references to irrelevant science and mathematics is a mere distraction. One that seems to have quite juvenile and unworthy motivations.

Inexact differentials enter thermodynamics in the production of work and heat. There is a change of state defined by end points but the path is unknown. This is opposed to ballistics where an exact path can in theory be calculated. It is clear that these processes relate to the former rather than the latter and some estimate is given of work and heat produced.

Is there a pattern emeging here of juvenile and irrelevant comment made from dubious motivation?

Look at the other journals where their papers on this general topic have been published:
Theoretical and Applied Climatology, Journal of Experimental and Theoretical Physics, Physics Letters A, International Journal of Water, Proc Roy Soc Series A.

Papers on other topics are published in Science, PNAS, etc.

This is not the publication record of a ‘crank’, it is actually a very impressive publication record.

Why have the biotic pump papers been published in Phys Lett without any apparent problem, but are resisted by the atmospheric sciences community? The point is that the physical reasoning is sound (which the physicists seem to get). The issues that the atmospheric scientists have are raised in the post (e.g.current climate models work fine, yeah right).

We can’t fully test this idea unless we formulate a general circulation model in multi-component multi-phase form, formally treating water as a separate component in a multi-fluid flow. I believe that we need to do this anyways, I have suspected for a long time that the very high water vapor feedback is an artifact of the approximations made regarding the water phase in the current climate models. These are not an issue on weather timescales, but accumulate over climate time scales.

So in my book, this hypothesis will remain as an open issue until something like I suggest above is done. Is their paper sufficient motivation for building such a model. Probably not for anyone outside their research group. But sorting out what might be going wrong with water vapor feedback and actually getting the moist thermodynamics correct in climate models should be a high priority. Instead, climate modelling efforts are moving in the direction of throwing more ancillary elements into an earth system modeling framework.

Again – inexact differentials apply equally to heat and work and entropy. There being some correspondence between these entities – and that the path between states is not definable by means of a functional relationship.

Given your inexact comprehension of basic maths and physics – and all inclusive links to a few quite irrelevant references – might not this require some futher consideration on your part?

A severe criticism of the Makarieva et al analysis — and perhaps a contributing factor in their article’s foggy physical reasoning? — is that their article’s notation (inexplicably!) does not respect this crucial thermodynamical distinction.

‘In thermodynamics, a state function, function of state, state quantity, or state variable is a property of a system that depends only on the current state of the system, not on the way in which the system acquired that state (independent of path). A state function describes the equilibrium state of a system. For example, internal energy, enthalpy, and entropy are state quantities because they describe quantitatively an equilibrium state of a thermodynamic system, irrespective of how the system arrived in that state. In contrast, mechanical work and heat are process quantities because their values depend on the specific transition (or path) between two equilibrium states.’

‘An inexact differential or imperfect differential is a specific type of differential used in thermodynamics to express the path dependence of a particular differential. It is contrasted with the concept of the exact differential in calculus, which can be expressed as the gradient of another function and is therefore path independent. Consequently, an inexact differential cannot be expressed in terms of its antiderivative for the purpose of integral calculations i.e. its value cannot be inferred just by looking at the initial and final states of a given system.[1] It is primarily used in calculations involving heat and work because they are not state functions.’ Both quotes rom wikipedia

‘The First Law is a conservation law,- Energy can neither be created nor destroyed. It requires that we balance the energy budget when we describe a change in state. A change in energy content (dE) is accompanied by the performance of work (w), and/or the transfer of heat (q) between the thermodynamic system under consideration, and its surroundings.’ http://www.life.illinois.edu/crofts/bioph354/thermo_summary.html

A change in energy is the system involves a change in state.

‘The description of entropy as energy dispersal provides an introductory method of teaching the thermodynamic concept of entropy. In physics and physical chemistry, entropy has commonly been defined as a scalar measure of the disorder of a thermodynamic system. This newer approach sets out a variant approach to entropy, namely as a measure of energy dispersal or distribution at a specific temperature. Under this approach, changes in entropy can be quantitatively related to the distribution or the spreading out of the energy of a thermodynamic system, divided by its temperature.

The energy dispersal approach to teaching entropy was developed to facilitate teaching entropy to students beginning university chemistry and biology. This new approach also avoids ambiguous terms such as disorder and chaos, which have multiple everyday meanings.’ again wikipedia

And of course I am aware of the notation used for exact and inaxact defiiferentials. The distinction between state and process variables are irrelevant to the discussion of exact and inexact differentials. They are quite seperates things. So your fallacy FOMBS is that of a red herring.

These are quite basic concepts of maths and physics and are indeed, again, irrelevant to the discussion.

yes, they can ignore it. The editor published it over the objections of reviewers. Objections that were not met. he thought the paper would generate interesting discussion. The IPCC summarizes the science.
What would they say “there is a paper that makes unsubstantiated claims”
Heck, there is a lot of grey literature that says all manner of crazy things.

You have gone off the deep end, Steven. What about papers that are rejected by a legitimate journal and then are shopped around, until they land in the pay-for-play journal of last resort. Box checked, no problem.

Reviewers don’t get to make the decision on what gets published. This paper’s box has been checked. Remember what that means?

Don, you write “What price will the IPCC pay for ignoring this paper, or any other paper they choose to ignore?”

Precisely. This is the point I think I am getting at. This paper is by no means unique this time around. It might merely be one of several they will have to ignore, in order to preserve the certainties which which they express their conclusions in the SPM to WG1 of the AR5.

If climate models would be built fully from first principles that would be relevant. In practice those parts of climate models where this paper would have some influence are in most cases not built from first principles but are presented by parametrizations made to agree with empirical data on the relevant subprocesses. A new theory does not change the empirical data.

Understanding of the physics of the atmosphere does certainly have its role also in choosing the parametrizations, but it’s difficult to see, how this paper would affect that even if it were true.

Don,
it’s pretty simple. The IPCC does a summary of the science that is relevant to the topic at hand. The FOD and SOD were open for review.
Anyone could be a reviewer. All a reviewer would have to do is put in a comment:
‘I think this paper is relevant to the claims you have made”
If the paper was relevant then the lead author would probably write something about it. This paper has been out there submitted for a long while. No skeptic made any comments to the authors that they overlooked it. Go figure. And it would be really hard to figure out how exactly it was relevant. As the editor said.. its not wrong and people should probably continue to discuss it. One cannot conclude anything from a ‘not wrong” claim. Now, if it correct, you might be able to show that models could be improved. But you would have to show that. basically, a ‘not wrong’ premise leads to no conclusion, at least in traditional logic.

“You have gone off the deep end, Steven. What about papers that are rejected by a legitimate journal and then are shopped around, until they land in the pay-for-play journal of last resort. Box checked, no problem. ”

Sorry but the results paper was not rejected by JGR. The paper was submitted. we withdrew it when they said they would not consider it until the methods paper published. results. methods. two different papers.

Handling water fully in a model based on fundamentals requires clearly a two-phase model as precipitation and re-evaporation are real significant processes.

The problem of this paper is that it does not handle the mathematics and its relationship with the physical system well enough. The weaknesses in that have made it possible for the authors to avoid seeing the errors in their reasoning and it makes it excessively difficult for the others to figure out exactly where the actual errors hide.

There are good reasons for the practice that the choice of free variables is specified explicitly in thermodynamic derivations and that the variables held constant are also often marked explicitly in the formulas that contain partial derivatives. There seem to be problems in the paper that have their origin in not following these practices.

It seems that a relatively simple physical model can be constructed to verify this theory. If verified experimentally, then construct a numerical model of the experiment and scale up from there.

One step at a time.

From my scientific perspective, Climate Science has been all about confirmation of a grand theory rather than solving small problems and figuring things out.

Obviously something needs to be done about GCMs when it seems every day we see more and more human forcings added on top of CO2 with absolutely zero ability to simulate the apparent low transient feedback sensitivity. Unless , of course, you crank up the aerosol knob to 11.

You are correct in that is not the publication record of cranks. Further, even if insignificant in magnitude, the effect (if real) would be at a minimum be an interesting excercise in theory and quantification. So what is the brouha about? Maybe it has something to do with what the paper MIGHT mean.

For example. it might mean that biotic-regulation must be taken very seriously. And it might mean that given a healthy, vigorous biosphere, the burning of massive amounts of fossil fuels is in fact relatively harmless. It might mean that significant ocean pollution or forest clearing threatens all life on the planet. It might mean a change in the status quo.

The impetus for crank science can from many quarters, meta-physics, religion, politics, money and/or power. It would be best for all of us refrain from lobbing the crank bomb and simply work on what the science DOES mean.

“The issues that the atmospheric scientists have are raised in the post (e.g.current climate models work fine, yeah right).”

Yeah, it’s like deja vu all over again. Nobody’s interested in working on chemical evolution models either. The current ones work fine (yeah right). The “current ones” are pretty much Miller-Urey from the early 1950s where he zapped a methane ammonia atmosphere in a flask with electric arcs for few weeks and got some amino acids to fall out. The concentration of organic molecules was far too dilute to do anything interesting. That requires concentration and there’s nothing but hand-waving speculation about a mineral lattice doing it. Nothing in nature has been shown able to concentrate the amino acids enough so they can start combining into interesting polymers. Just as bad, the atmosphere Miller used is now thought to be probably not what the early earth’s atmosphere was like. An alternate model, RNA-first, is in a similar state but the can’t figure out how nature could make all four that are needed nor can they figure out how nature could concentrate them sufficiently. Without concentration of the reactants any lucky two or three unit polymers that form fall apart before they bump into more base units. And polymers hundreds of bases long configured just perfectly to have any chance of doing anything interesting. It’s a pretty pathetic narrative when you look behind the curtain. All that’s really fairly sound science is common descent and then just handwaving about how novelty is generated as descent happens. Recombination, sure. There’s a fair amount of plasticity. Nothing new needs to be invented to go from a shrew to an elephant just rearrangements of parts, sort of like cannabillizing a couple motorcylces to make an automobile. But try to get a description of how something harder happened, like how did prokaryotes turn into eukaryotes. What’s the path to go from a bacteria with circular DNA an no nucleus to the packed structures isolated inside a cell nucleus?

The answer is “It must have happened somehow because evolution is true”. Global warming works that way too. Like how can there be this pause we’re seeing when the accepted range of climate sensitivity and GCMs can’t duplicate it without subtracting CO2 induced warming. Well, it just had to happen somehow because CO2 induced warming is true. No doubt is cast on the truth of the underlying assumptions. They’re true by fiat. Hail to the climate kings.

I’m not sure it was the larger point you were trying to make, but the thing that jumps out at me from this post is the difference in reactions between Climate Science(TM) and other scientific groups. A very non-scientific reason, but it still smells like rat.

Precisely Qbeamus!
I note this phenomenon in practically every discussion on climate I see. In general skeptics seem to use discourse appropriate for scientists discussing science while true believers seem to prefer discourse appropriate for politicians discussing politics.

I cannot judge the scientific validity, as you can, but it appears to me that this needs further investigation.

You mention the need for model simulations “formally treating water as a separate component in a multi-fluid flow”. This could possibly clear up some of the present uncertainty surrounding water vapor (and cloud) feedbacks.

Wouldn’t it also be appropriate to look for actual empirical evidence to either validate or falsify the hypothesis that precipitation drives winds, as Anastassia Makarieva has suggested?

I admit unease with making any claim based on the status or authority of the authors. It is absolutely true that Anastassia has an impressive publication record. But should that be relevant here in any formal sense? Its the same issue with us being outsiders or insiders of the mainstream, or what we think of global change. While I am sure these factors — or the perceptions of them — have influence, shouldn’t we be striving for objectivity based on the value of the ideas? How does this impact young scientists and their choice of disciplines? As an outsider I think climate science needs to be a little more open and a little less defensive — less preoccupied with authority and more with ideas. I do fully understand that it is hard to do: there is so much we could be looking at that we need easy ways to filter it. But a more open attitude and a more level playing field looks desirable from where I am. Just a thought.

“Why have the biotic pump papers been published in Phys Lett without any apparent problem, but are resisted by the atmospheric sciences community?”
You were part of the resistance.. Perhaps you can answer.

Read my review, and read my previous statement, not to mention consider the fact that this is the 2nd post on this topic on my blog. I clearly do not dismiss this, whereas others are prepared to dismiss it.

Is that all this paper is about? Land use changes the way things move heat about. So if you look at the surface albedo and see “TREES”, you might want to think mobile heat capacity instead of radiant forcing, at least inside a moist air envelope.

It’s difficult to get hold of the reasoning as the normal order of looking at the processes is reversed.

The normal way of considering the role of adiabatic condensation in ascending air and how that’s related to pressure and temperature changes goes essentially as follows:

1. the air ascends
2. the pressure and temperature are decreasing
3. the decreasing temperature makes saturated vapor condense releasing latent heat
4. the release of latent heat makes the drop in temperature smaller but cannot reverse the sign of the change
5. the pressure is not affected by the condensation as the pressure is determined by the surrounding atmosphere (we are considering an adiabatic process and that’s slow enough for that)

The above points describe essentially similar changes as the paper discusses in chapter 2 except for one essential difference: The only source of pressure drop is the ascending movement of air not to the condensation of water.

As I started this comment it’s difficult to get hold of the whole argument of the paper, but so far I have concluded that the fault is in the handling of the pressure changes in the atmosphere. The pressure of a volume of gas in atmosphere is not determined by what happens in that volume but by the atmosphere outside that volume and in particular by the mass of air above that volume in the simplest case.

The real atmosphere is not that simple when circulation is taken into account. The paper purports to tell where the winds come from, but the analysis does not present any self-consistent picture that could describe the overall circulation and winds.

The mathematics presented does not describe what happens in ascending moist air. The formulas do not apply to the process they are supposed to describe. There’s confusion on what’s changing and what’s not. The calculations should have been made using partial derivatives and defining always carefully what are the free variables. When that’s not done at every step thermodynamic derivations are usually wrong as they seem to be in this paper.

Going trough the argument I feel confident that something essential is missing. (I have sometimes erred while equally confident, but being in such a good company makes that less likely in this case). Figuring out from a paper where the gap in logic is, is often much more difficult than getting convinced that something is missing, when the paper does not present all steps of reasoning explicitly and does not describe precisely, how the equations are connected to the physical system that’s being discussed. It’s not surprising that papers that seem to be wrong leave also gaps in the reasoning.

It’s true that many good papers are also terse and difficult to understand by non-specialists. They are, however, written following practices of the particular field of science and thus accessible to other scientists of the same specialty. From the list of publications of Makariaeva we see that she has been very productive and published in a variety of fields. People with such a coverage may well end up writing articles that are not easily accessible by anyone – positively or critically.

To define the output of models as empirical evidence is to misuse the term. This is especially so where the models are based on nonlinear equations. Simple energy models such as the one presented seem much more useful in developing a theoretical understanding of these processes which remain unsolved in a realistic understanding of the limits of current sceince.

‘Finally, Lorenz’s theory of the atmosphere (and ocean) as a chaotic system raises fundamental, but unanswered questions about how much the uncertainties in climate-change projections can be reduced. In 1969, Lorenz [30] wrote: ‘Perhaps we can visualize the day when all of the relevant physical principles will be perfectly known. It may then still not be possible to express these principles as mathematical equations which can be solved by digital computers. We may believe, for example, that the motion of the unsaturated portion of the atmosphere is governed by the Navier–Stokes equations, but to use these equations properly we should have to describe each turbulent eddy—a task far beyond the capacity of the largest computer. We must therefore express the pertinent statistical properties of turbulent eddies as functions of the larger-scale motions. We do not yet know how to do this, nor have we proven that the desired functions exist’. Thirty years later, this problem remains unsolved, and may possibly be unsolvable.’ http://rsta.royalsocietypublishing.org/content/369/1956/4751.full

Pekka’s fallacy – btw – is the argument by way of demanding impossible perfection. 1st by way of unsatisfiable gut feelings – and secondly by way of complaining that the unsolvable has not been solved and therefore the concept is likely to be wrong.

So based on my understanding of water I state:-
Now lets have a simple water and N2 atmosphere. Initially, all the molecules are bashing each other and pairs of hydrogen bonding water molecules are broken before they are hit by a third slowly moving water molecule.
As the temperature falls the statistical possibility for pairs of water molecules to form increases, and so there is an increased possibility for a slow speed collision between a pair and single water molecule. All of a sudden we have three hydrogen bonded water molecules. The three water molecules require a fast moving molecule hitting them to be broken up, but can capture a range of slower moving water molecules. And so it goes, the bigger the hydrogen bonded water cluster, the easier it is to form a bigger cluster. You make use of this positive feedback nucleation cascade in a cloud chamber.

Now what I do not know, and would like to know from you Pekka is this, based on your two points.

For point 3). How do growing nucleation sites emit ‘latent heat’. In what form is this energy? Is it infrared radiation? If so, what is the spectra of this radiation?

For point 4). I was under the impression that Boyles law was at work. As the water undergoes a phase transition both pressure and temperature will drop. How can you be so certain that the ‘small’ drop in temperature isn’t due to a large change in pressure?

Doc, thank you for the questions. Particularly your 2nd to last paragraph questioning point 3. I

Naively, the hydrogen-bonded water droplets might lose some or all of their energy (latent heat) via IR radiation as the energy in the molecular orbitals drops to a lower level (??)

Alternatively, it is only the water molecules already at the statistically low end of the kinetic energy distribution which condense? Thus at a molecular level no energy is transferred, but the latent heat release is a result at the thermodynamic level?

Or, the kinetic energy of the water vapor molecules is carried over into the droplet somehow, but quickly dissipated to the gas molecules via collisions occurring immediately after the condensation?

There is an attraction between water molecules. That means that the energy of a water molecule with the same kinetic energy is lower in liquid than in gas. When a molecule comes from gas and gets stuck in the liquid, energy is released. Originally that energy goes to kinetic energy of molecules in liquid but soon it’s shared also with the surrounding gas when gas molecules bounce from the liquid.

When water is condensed in constant volume (like in a closed bottle) the pressure drops and temperature is raised as potential energy is released.

When water is condensed at constant pressure the volume is decreased and temperature raised again. This is the process in atmosphere.

When the condensation of saturated water vapor is driven by decreasing temperature some energy is released again but less than is taken by the process that leads to the decrease of the temperature. In ascending air the temperature is lowered by adiabatic expansion as heat is transferred to work that the expansion does in pushing other air out of way.

the energy of a water molecule with the same kinetic energy is lower in liquid than in gas

not sure I understand

When a molecule comes from gas and gets stuck in the liquid, energy is released. Originally that energy goes to kinetic energy of molecules in liquid but soon it’s shared also with the surrounding gas when gas molecules bounce from the liquid.

this i do understand. see what I wrote above “Or, the kinetic energy of the water vapor molecules is carried over into the droplet somehow, but quickly dissipated to the gas molecules via collisions occurring immediately after the condensation?”

The part that you are “not sure you understand” is just another way of saying the same thing that you understand. It’s just based on the notion that the energy of the molecule is the sum of the kinetic energy and potential energy of the interaction between molecules.

The term “orbitals” refers normally to the state of electrons, not atoms of a molecule. The electronic transitions occur usually at higher energy, typically at X-ray energies, but sometimes at UV or visible light.

Molecules in gas have discrete vibrational and rotational states that are related to visible, IR and microwave radiation. Molecules in liquid don’t have such clean discrete states but they do still interact more strongly at frequencies close to such vibrational states. The states are not discrete because neighboring molecules are so close to each other that no vibrational state has time to fully form before it’s destroyed again.

Both GH gas molecules and molecules in liquid emit and absorb IR, but an excited molecule in free space may live rather long before it emits radiation. States of CO2 that radiate 15 µm IR have a lifetime of around 0.5 seconds in free space. The time between collisions is by a factor ob billion shorter than that.

The lifetime is only average. Thus one molecule in billion does emit radiation before next collision. There are all the time billions of billions CO2 molecules in vibrationally exited state in a small volume of air. Thus there’s a lot of emission going on in spite of the fact that only one case in billion leads to that.

‘There is an attraction between water molecules. That means that the energy of a water molecule with the same kinetic energy is lower in liquid than in gas. ‘

I have no idea what this means. I know that during a phase transition there is the release of energy, I wish to know what for this energy is in.

‘When a molecule comes from gas and gets stuck in the liquid, energy is released. Originally that energy goes to kinetic energy of molecules in liquid but soon it’s shared also with the surrounding gas when gas molecules bounce from the liquid.’

Are you saying we observe loss of energy from the droplet in the form of infrared radiation? If that is your contention, then I don’t understand the next part of your description.

‘When water is condensed in constant volume (like in a closed bottle) the pressure drops and temperature is raised as potential energy is released.’

How can the temperature rise? The kinetic energy in the system has been transformed by the phase transition into infrared light, photons. These photons will generally escape the volume as liquid and gaseous water have low absorptions. A large fraction of these photons will go up and off into space.

Infrared radiation has a negligible influence on what happens to molecules in air. (I just wrote a comment describing that as something like one part in billion). IR is important on macroscopic scales, not on micro scale.

The binding energy between molecules in liquid is essentially a form of chemical binding energy. In case of water molecules it’s strong enough to make two-molecule dimers stable in free space (but very easy to break up by weakest collisions).

In phase transition from gas to liquid chemical energy is released exactly as chemical energy is released when fuel burns. Only the quantity is less.

These sorts of explanations on a molecular level I think are important to this discussion. There are many here who understand classical thermodynamics but don’t try to understand this stuff. For me, it is helpful in the climate context to clarify thermodynamic or meteorological concepts using energy conservation at a molecular scale. Of course, the answers or translation to the phenomena on a large scale usually necessitate empirically (experimentally) determined coefficients to partition energy transfers.

“This paper considers the emission of infrared characteristic radiation during the first order phase transitions of water (condensation and crystallization). Experimental results are analyzed in terms of their correspondence to the theoretical models. These models are based on the assumption that the particle’s (atom, molecule, or cluster) transition from the higher energetic level (vapor or liquid) to a lower one (liquid or crystal) produces an emission of one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particle in the new phase. Based on experimental data, the author proposes a model explaining the appearance of a window of transparency for the characteristic radiation in the substances when first order phase transitions take place. The effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth’s cooling; formation of hailstorm clouds in the atmosphere is accompanied by intensive characteristic infrared radiation that could be detected for process characterization and meteorological warnings. The effect can be used for atmospheric heat accumulation. Together with the energy of wind, falling water, and solar energy, fog and cloud formation could give us a forth source of ecologically pure energy. Searching for the presence of water in the atmospheres of other planets might also be possible using this technique. Furthermore, this radiation might explain the red color and infrared emission of Jupiter.”

I hadn’t seen that and it’s difficult to tell what’s its relevance really is. I tried to find other papers on the subject but found very little that’s not authored by Tatartchenko and Perel’man alone or with coauthors . One master’s thesis and a article written by Chinese authors (both written in very bad English) refer to this paper. The earliest articles by Perel’man are from the early 1970’s.

Judging by myself the value of the paper is beyond my interest. Thus lacking further significant information on that I’m just not convinced that the phenomenon is as important as Tatartchenko implies. It’s to be expected that IR can is emitted and absorbed at phase boundary when molecules move from one phase to the other but it’s not at all obvious that the effect is really significant. I would expect that a major effect would appear in various empirical data sets and that the effect would therefore be well known, if it were so significant.

One factor that seems to influence against its importance is the frequency range that’s rather high for thermal radiation. Thus it may be a relatively major source of IR at those frequencies without any significant influence on the total energy balance.

Pekka, at the moment the water cycle appears to consist of sensible heat causing the liquid to gas phase transition, water molecules rising, water condensing and releasing the latent heat as molecular collisions.

However, if even a small fraction of the latent heat is converted directly into infrared photons it changes the energy flow through the system; the Earth is cooled as IR generated in the atmosphere.

If I were a physicist I would know or be attempting to find out what from of energy transduction occurred when water gave up its latent heat during the phase transitions.

If that effect is significant it manifests itself very clearly in the spectrum of the IR radiation leaving the atmosphere. There would be a significant excess in IR radiation in rather wide peaks around 1.537 µm and 2.1 µm or in terms of wavenumbers around 6500 1/cm and 4761 1/cm. Normal thermal radiation at these wavelengths is extremely weak, solar radiation is much more important. The paper tells that the peaks exceed the background radiation by a factor of ten. The background thermal radiation is, however, at these frequencies only one millionth of the peak value or less. Thus the importance seems to be 10/1000000, or totally insignificant.

This is the conclusion at the moment and that would explain well, why this phenomenon has not raised more interest.

“in order to lift a moist air parcel, you must draw a dry air parcel down: this is what circulation is about.”

I don’t think that can be right because water vapour is lighter than air.

Thus a parcel of air into which water vapour is injected will rise without any change in ambient temperature.The reduction of density from surface upwards is what initially reduces air pressure as measured from the surface.

The circulation starts with that initial uplift. At the point of condensation the corresponding descent begins in order to complete the circulation.

Condensation might release energy and reduce pressure locally but the increase in density of the air bereft of water vapour plus the drawing in of similarly dry air from the sides will result in a recovering air pressure as measured from the surface.

You can’t reduce surface pressure when evaporation occurs then reduce it again when condensation occurs.
It would be a neat form of perpetual motion machine though.

“in order to lift a moist air parcel, you must draw a dry air parcel down: this is what circulation is about.”

I don’t think that can be right because water vapour is lighter than air.

Ah, I thought Anastassia was including that in her circulation.

I’ve just read judith’s: “Why have the biotic pump papers been published in Phys Lett without any apparent problem, but are resisted by the atmospheric sciences community? The point is that the physical reasoning is sound (which the physicists seem to get). The issues that the atmospheric scientists have are raised in the post (e.g.current climate models work fine, yeah right).”

I think the reason “atmospheric scientists”, I’m putting this in quotation marks because I think this refers to “climate scientists” whose basic physics I dispute, are resisting this is really quite simple, it includes condensation and as I’ve gone to some effort to explain, the Water Cycle is missing from the energy budgets and I give the following as examples of their narrative:

“Two processes remove CO2 from the atmosphere: photosynthesis by land plants and marine organisms, and dissolution in the oceans.”

In other words there is no rain in the AGWGreenhouseEffect’s carbon cycle. You can hardly expect people with no rain in their world to argue rationally about this paper which postulates condensation driving winds.

“This H2O negative-feedback effect on CO2 is ignored in models that assume that warm moist air does not rise and form
sunlight-reflecting clouds, but remains as humid air near sea level, absorbing infrared radiation from the sun, and
approximately doubling the temperature rises predicted from atmospheric CO2 increases. This false positive-feedback
(amplification) due to the assumed non-bouyancy of warm air is vital for greenhouse effect climate disaster predictions”

The climate models don’t have any mechanism for producing the clouds they argue about; they don’t have any gases bouyant in air, not even water vapour which as you say is anyway lighter than air.

I continue to find the varied input in such discussions confusing, I think it’s mainly because there is no solid agreement on the basics. So for example, some throw in that the paper is giving standard already well known to meteorology, but this is clearly, from my two examples above, not the case that this is standard or well known for “climate scientists”.

This is, I agree, a thought-provoking paper, however, I feelthere are substantive misinterpretations of the physics.

First, it is inappropriate to consider the hydrostatic relationship as anything but that which the vertical pressure distribution will equilibrate to when forcing is removed. The real relationship, as I show in detail in my modeling book,

is that the hydrostatic assumption is only accurate when the vertical acceleration is much smaller than magnitudes of the buoyancy and the vertical pressure gradient force. This is easier to achieve when the horizontal scale of a circulation is much larger than the vertical scale. Scales larger than a few kilometers are always essentially hydrostatic in their pressure distribution.

Thus, equation 2, for example, does not appropriately represent the physics.

Second, I agree – when precipitation occurs, mass is removed. This is an important issue raised by Anastassia, Victor and colleagues. This will create a density (mass) reduction in that column, which will result in small scale dynamic pressure effects (i.e. producing acoustic waves) as the atmosphere adjusts to the new spatial distribution of mass. There is no partial vacuum, however. I recommend several of our papers where Mel Nichols and others have examined this issue in considerable quantitative detail –

Removing water by precipitation will lower the pressure in that column but only as this process continues. On spatial scales of a few kilometers and larger, the system will be very close to hydrostatic balance even with this effect. Even for smaller scales, except for the most vigorous convective motions, the dynamic pressure is still only a small fraction of the hydrostatic pressure.

The drop in pressure if all of it was suddenly removed, would be significant. Consider that at sea level the weight of the atmosphere (the hydrostatic pressure) is equivalent to about 10.3 meters of water. Precipitable water (the amount in a column of atmosphere if it were all condensed out) is almost always less than 0.0635m (a near record value).

If the surface pressure were 1000mb than the reduction in pressure would be 993.8 mb. However, i) all of this water would not be removed, and ii) air would flow in as soon as the pressure started to fall. If this fall in pressure is what the authors mean, I agree this is an interesting issue.

However, its response would be essentially a hydrostatic response and not from a “partial vacuum”. It would be straightforward to test this with modeling by calculating the pressure change over a region due to the hydrostatic pressure changes due to the removal of precipitable water by precipitation. In one run, ignore this effect; in the other run include it. In RAMS runs, we account for this loss of mass in calculating the pressure fields.

I very much agree with Pielke that the effects of condensation and precipitation upon the pressure field operate on far smaller scales, both spatially and temporally, than Makarieva et al. imagine. After all, both processes are quite highly localized. Thus on the scales of Benard cells and tornadoes and perhaps up to those of cyclones, convection in particular should be affected by their mechanism. At the scales of the Walker circulation and quasi-permanent features such as Hadley cells and the Azore high, however, this mechanism must be negligible. Certainly it does not drive the geostrophic winds. At best their theory will find realistic application in modeling local weather rather than planetary climate.

‘Most circulation patterns on Earth are much wider than they are high, with the ratio height/length being in the order of 10-2 for hurricanes and down to 10-3 and below in larger regional circulations. As a consequence of mass balance, vertical velocity is smaller than horizontal velocities by a similar ratio. Accordingly, the local pressure imbalances and resulting atmospheric accelerations are much smaller in the vertical
orientation than in the horizontal plane, the result being an atmosphere in approximate hydrostatic equilibrium (Gill, 1982). Air pressure then conforms to the equation…’

So the first part of Roger’s comment is addressed in the proviso that this applies to systems where the horizontal scale exceeds the vertical. Most circulation systems that is – Including Hadley cells – and all the major rain bearing cloud morphologies.

Thank you for your comments. I would like to once again most gratefully acknowledge your previous discussions of the relevant physics with us.

Equation (2) in the post does not presume a violation of hydrostatic equilibrium. Moreover, all the derivations are made assuming that the hydrostatic equilibrium is exact. (Minor deviations observed in the real world will not change our derivation).

Rather, Eq. (2) describes the (observed) non-equilibrium distribution of water vapor. If water vapor was the only gas in the atmosphere and obeyed this distribution, this upward pressure gradient force would make the gas accelerate up to very high velocities. A similar one-dimensional flow is observed on a small (laboratory) scale in the so-called heat pipes. The vapor accelerates from the hot end of the pipe, where there is evaporating liquid, to the cold end of the pipe where the vapor condenses. Velocities resulting from condensation-induced pressure gradient are huge, which determines the high heat transfer coefficients of these devices.

In the atmosphere the flow is three-dimensional, the water vapor is not alone and there is hydrostatic equilibrium. But still water vapor undergoes condensation and features a non-equilibrium distribution. Our proposition is that the potential energy released per unit time from vapor condensation (which is most visible in the 1-D case) is also present in the 3-D atmosphere. It is described by q (3). Because of hydrostatic equilibrium, vertical motions cannot be significant. Thus, all this potential energy produced goes into horizontal pressure gradients and horizontal winds, as per conservation energy equation (4).

So we agree with you fully that the hydrostatic readjustment is a key process. Namely this process leads to the formation of horizontal pressure gradients that we estimate.

Regarding the investigation of this effect in current models our view is that there are theoretical caveats, some of which we described in our blog. Additionally, because of condensation there is always a pressure readjustment in the column that occurs independently of the droplet fallout. (E.g., recently Spengler et al. (2011) addressed this problem in a 1-D numerical simulation.) So simply removing or adding precipitation (i.e. modifying the ∂p/∂t term as per the mass sink studies) does not, in our view, capture the relevant physical difference between a condensing and a non-condensing atmosphere.

Regardless of the rights and wrongs of the actual paper, I find it to be an extremely valuable paper. I believe the editors chose to publish it for the very reason that it puts new ideas about what drives climate out there – right or wrong, it has people thinking about things they otherwise would not and that is a good thing.
While the effects described may be small as some have suggested, it may also be the case that these small variations are at least in part responsible for “natural variation” – an area that seems well overdue for investigation.

We are rightly suspicious of monocausal explanations. And, there is not enough computing power on Earth to resolve a model embodying all of the relationships even if we knew all the variables. The real problem is, Western academia refuses to abandon a monocausal explanation for global warming and the reason for that refusal lies outside of science.

Enormous uncertainties persist with respect to the role of clouds in climate change. Moreover, models that strive to incorporate everything, from aerosols to vegetation and volcanoes to ocean currents, may look convincing, but the error range associated with each additional factor results in near-total uncertainty. Yet, there is a greater concern. Throughout the history of science, monocausal explanations that overemphasize the dominance of one factor in immensely complex processes (in this case, the human-induced emissions of greenhouse gases) have been inevitably replaced by more powerful theories.Philp Stott

It’s funny to read all the messages here that express belief that this paper has got so much criticism because it would put climate science in doubt, and be a problem for IPCC.

I cannot see, how that would be true even if the paper would be right. The paper is not about climate or climate change but about dynamics of the atmosphere on short time scales. It might affect models used for weather forecasting and dynamics that occurs at a level that’s not described in most climate models at all.

Your points seem generally true to me. However, I believe that if the paper were to provide support for significant biotic regulation of temperature then that would also diminish CO2 sensitivity. So, that does not pose a problem per se, depending upon IPCC objectves.

It is true that these miroprocesses of evaporation, condensation and cloud nucleation are not included in models as deterministic equations but are included as paremetisations. Getting the parameters right is of course one test of the plausibility of the model.

The other of James McWilliams tests of plausibility is ‘a postiori solution behaviour’.

Additional couplings introduce futher structural instability into the models – but presumably the subjective expectations about the range of plausible solutions would remain.

Peika said, ” It might affect models used for weather forecasting and dynamics that occurs at a level that’s not described in most climate models at all.”

well, if it turns out to be useful for weather forecasting and dynamics at that level, perhaps it would prove useful in reducing the rather large uncertainty the GCM have with clouds and aerosols?

This spreading effect they mention is kinda like that “ground plane” issue I have asked about. How with increased temperature the average altitude of the start of condensation would lower and that the lower cloud base would stimulate upper level convection and advection. That is one of the issues with a radiant model based on a moving “surface” I pointed out, Frame of Reference and all that.

Now if the models do accurately model the cloud dynamics, reduction in average cloud height, increased rate of upper level convection and the impact of advection on the radiant “resonance” I think it is called, this paper is a complete waste of time :)

The issue is that scientists don’t like grandiose claims that imply that they have been stupid. When they see such claims they require good arguments to support the claims, and keep on protesting when no good arguments are given but the claims have not been withdrawn and even presented again trough getting published.

Of course most scientists don’t like the grandiose claims that imply they have been stupid and that’s the point – good science can be and is rejected only because it implies that the orthodoxy has been stupid. And bad science is protected and cheered if it’s consensus, no matter how stupid.

Edim, you write “I agree. The warmists are for some reason concerned and protest too much.”

Is this reminiscent of the furor over the original paper by Livingston and Penn? This was rejected for publication, and the authors were persuaded to publish it on line. It has now been amplified, and published in a proper journal. It was about sunspots, and only peripherally about climate, but the rumor was that the implications for a potential Maunder type minimum was the main reason why the paper was rejected in the first place.

Steven Mosher | February 1, 2013 at 12:03 pm |
“Simple question; How can an averaged result be incorporated in differential equation maths?
Your possible answers are.
1. Show how
2. Say it cant be done.”

Steven, I thought it might help if you clarified your idea of “SUBSTANTIVE”. What do you mean? What will satisfy you? For example, with this question you sound like you (and Nick) have something significant in mind. What is it?

All the equations are written in the differential form. They are there to be solved. The fact that they are applied to final volumes in the real world is no news. What “averaged result” do you want to incorporate and where?
Of course it is possible to take any argument irrespective of its relevance and appear as if you found a crucial error. But it is not very productive.

Steven Mosher | February 1, 2013 at 11:46 am | Reply
“In short, it cannot be incorporated into other science until the issues are addressed in a SUBSTANTIVE way.”

I think that it might clarify the situation also with the question why our paper was accepted if we undertake the following exercise. Let us take a paper which Nick Stokes and, by inference, Steven Mosher are comfortable with (find it SUBSTANTIVE) and see the difference with ours. We have one such example, it is the hurricane model of Bryan and Rotunno (2009). It is mentioned in the post and was mentioned in previous discussions at the Air Vent and, if I am not mistaken in my recollections, Nick praised it.

In this model the standard set of equations plus some additional numerical schemes are combined to find the dependence of some variable of interest (in this case, hurricane velocity V) on other variables and parameters, of which one is the turbulence length scale hl. We can for simplicity formulate this as V =f_1(hl), with function f_1 determined by the system of equations that are solved in the model. So, V=f_1(hl) is what the model produces. If we knew hl (e.g. if we take it from observations), we could predict V.

But the key problem is that hl is not an observable parameter. Nobody knows how to measure it experimentally and independent of V. So what is done in this model, this parameter is instead chosen such that the value of V the model produces matches the observations. But as we have chosen hl such that model-derived V matches the observations, we can no longer test our function f_1 that relates hl to V — is it at all reasonable? Thus, we cannot judge about whether the model physics is right or wrong. The model is not falsifiable. This is what we meant when we wrote that models are not physically based but calibrated.

Now let us turn to our work to see where and how it differs. We apply some physical arguments to get a relationship that links the dynamic circulation power q (3) or Q (5) to observable atmospheric parameters. We can write it, for example, like Q = f_2(P), where P is precipitation. We show in the ACP paper that function f_2 can be obtained in two ways: by making a couple of entirely plausible assumptions about condensation rate S or directly by considering the non-equilibrium pressure gradient of water vapor as per Eqs. (1)-(3) in our blog. Nick has been actively challenging our first derivation, he does not find some of our arguments plausible. That’s fine and constructive, and all of his specific points are well taken. Now then, on the basis of these criticisms, Nick perpetuates the idea (that looks SUBSTANTIVE to Steven) that our results are wrong and have been manipulated or “made up”. I am not certain about this last quote, but I recall having seen it somewhere, so if this is not true, I apologize in advance.

However, any interested reader can see at once that there is extremely little space for manipulation in our approach. There are only four key variables: vertical velocity w, water vapor pressure pv, and the two scale heights hv and h. They are all perfectly observable and measurable and combine elegantly to give an estimate of circulation power. Thus, even if someone, like Nick, is not convinced by how we derived our function f_2, the validity or invalidity of our propositions can be easily checked by empirical evidence — the ultimate criterion of truth in science.

This is a possibility which is lacking in our counter-example of the hurricane model (which, in contrast to ours, Nick and Steven find SUBSTANTIVE). There is no way of determining of whether function f_1 (which summarizes the model physics) is valid or not.

Such an empirical check in our approach is facilitated by the fact that both w (vertical velocity) and pv (water vapor pressure), and hence precipitation P, vary within wide limits in the atmosphere. So if our function f_2 were wrong, by changing the key variables greatly the prediction of circulation intensity that it yields must go weird.

But what do we observe instead? Instead we observe that f_2 yields meaningful predictions over a very broad range of precipitation values. No existing model demonstrates such a skill. If you think a moment, it’s really impressive. Is such a result worthy of publication? Certainly, yes.

This is what I speculate might have played a role in our paper getting published. The paper itself can be poorly written and have too many equations, the authors can be confused about some less essential points, they may have made a terrible error of writing heat dQ instead of entropy dS in an otherwise adiabatic equation, but having spent two years on disentangling this mess, the Editors might have became certain that the result is there. And it is important.

In the long run, that openness might bring good results, Anastassia Makarieva! Because it is evident (to everyone) that you have tackled an interesting problem. What is less evident (to everyone) is whether your mathematical methods are valid, and/or your inferences are logical, and/or your conclusions are correct.

Don’t let another two years go by! Post a longer, clearer, better-validated analysis to the arxiv!

It is clear that comparison of you to Kyuna – a cutesy, bubble-pop, Korean pop princess is well warranted.

It is less clear that you have any command of, maths, physics or natural philosophy. Greater horror still is the repetition of your eggregious bad faith.

Please no one has shown any fault in the maths or physics. Roger suggested it was different in very systems – but that was specifically excluded to concentrate on major systems. Pekka is going wit his gut. Steven is demanding that it be numerically modelled before it becomes real for him. What did we do before computers? And you are really quite silly.

Fan’s deliberate mischaracterization of Dr. Makarieva’s comment seems to me to have gone beyond the bounds of courtesy. His repeated posts also seem to have gone beyond the rules against spamming. I’m embarrased, on hehalf of the forum denizens, and I apologize on his behalf to Dr. Makarieva.

Not at all Kyuna – they are merely examples of your eggregious bad faith following silly comments on inexact differentials and Legendre transforms in thermodynamics. Someone might take you seriously – but someone who combines cluelessness with a bubble-pop princess persona does it for me.

So perhaps the wisest course of Makarieva and her colleagues, is to recruit a strong mathematician to: (1) repair the article’s bad/(wrong?) notation and then (2) repair the article’s imprecise/foggy/(wrong?) reasoning.

Too many elements of (thermo-) mathematical maturity are missing from the Makarieva et al. manuscript, and missing too from critical reviews of it … and missing especially from skepticism of climate-change physical science in general!

That is why climate-change skeptics especially should study and practice assiduously the elements of (thermo-) mathematical maturity. Doesn’t that plain advice amount to pure scientific common sense, Tallbloke?

If dear – you used the wrong term in nit picking Tallbloke. This assumes that there is anything at all relevant – instead of the wildly improbable – indeed quite claims on inexact differentials and Legendre transforms in thermodynamics. To add to that we now have Arthur C Clarke and Ruppeiner geometry via wikipedia. It has all the hallmarks of an internet search for terms that include thermodynamics and links to things that on inspection turn out wholely irrelevant to the issue a hand.

It leaves the impression of comments motivated less by truth and science and more by some psychological disorder. That it is all delivered in a cutesy, bubble-pop princess persona is bizarre.

Anastassia and co-authors, it comes down to whether you believe undilute ascending air parcels follow the moist adiabat which requires latent heat release in its derivation from the thermodynamical equations. If this is not your field of research, you may not have realized that the moist adiabat is central to understanding atmospheric convection and is now routinely used by weather services successfully to estimate updraft buoyancy, or convective severity, and to predict cloud-top heights. The concept of CAPE (convective available potential energy) is a well established consequence of the moist adiabatic lapse rate, and CAPEs over several thousand J/kg correspond to strong updrafts and severe convective situations when they are seen in atmospheric soundings, especially in conjunction with vertical shear that helps organize the convection into long-lived cells.

Jim, we are aware of CAPE. In our paper a whole Section 3.4 is all about comparing our effect with CAPE.

“CAPEs over several thousand J/kg correspond to strong updrafts and severe convective situations when they are seen in atmospheric soundings, especially in conjunction with vertical shear that helps organize the convection into long-lived cells.”
Yes, but as we discuss in the paper on p. 1045, very strong moist updrafts form in low CAPE environments as well. This suggests that perhaps CAPE is not the thing that actually decides.
The point I made several times in this thread is that CAPE calculated for the ascending parcel is not a measure of potential energy available for circulation because of the energy losses in the descending branch. (When the parcels that descend dry adiabatically become warmer than the environment.)

‘In meteorology, convective available potential energy (CAPE),[1] sometimes, simply, available potential energy (APE), is the amount of energy a parcel of air would have if lifted a certain distance vertically through the atmosphere. CAPE is effectively the positive buoyancy of an air parcel and is an indicator of atmospheric instability, which makes it very valuable in predicting severe weather. It is a form of fluid instability found in thermally stratified atmospheres in which a colder fluid overlies a warmer one.

While I was there – wikepedia had a nice little animation.

A skew-T plot showing a morning sounding with a large hydrolapse followed by an afternoon sounding showing the cooling (red curve moving to the left) which occurred in the mid-levels resulting in an unstable atmosphere as surface parcels have now become negatively buoyant. The red line is temperature, the green line is the dew point, and the yellow line is the air parcel lifted.

Btw – Anastassia thank you – and what a beautiful name you have.

There was a bit of discussion about disciplines. A broad knowledge is essential to understanding just about anthing in climate. Narrow disciplines are just so 20th Century.

Unfortunately the discussion in your sections 3.3 and 3.4 is mistaken because when you create the dry and moist columns you apply a diabatic cooling process (like refrigeration) which is an entropy reduction. This would be OK, except different coolings are applied to each column. As we know, cooling at constant volume (constant height of the columns) leads to a pressure reduction and so the dry column which becomes cooler should have lost more pressure than the moist one in this diabatic process. Taking this into account, you would have seen that the pressure effect you are looking at is smaller than that due to your cooling process that you neglected. The net effect is consistent with the idea that latent heating has a bigger positive pressure effect than vapor reduction’s negative effect.

In ‘The Australian’ newspaper today,Feb 2,, 2013, almost a half
page coverage ( p22) of ‘Where the Winds Come From’ under
the heading, ‘Branching out on climate’…. a theory based on the importance of forests iis threatening the established ideas. The
article includes comments by Douglas Shiel. professor of forest
ecology. Would this theory have received media publicity 3or 4
years ago, I wonder?

a) The same amount of water vapour in condensed form and b) That initial quantity of air and c) More air and water vapour imported from the surroundings.

Isn’t ii) going to be heavier than i) for a net increase in surface pressure ??

What has happened is that a nominal pressure reduction locally at height caused by contraction has imported more molar material into the original volume for an increase in pressure at the surface below.

how do you explain several prominent features of the global wind field?
1. winds are strongest above mid latitude oceans
2. there is a sharp drop in wind energy at continent boundaries
3. winds are low above continental areas except over deserts
4. winds are weakest over the tropics where precipitation rate is highest
5. the windiest continent is Antarctica, also the driest

Thank you for your question. Let me give some context to my replies below. Our theory constrains the rate at which the kinetic energy of winds is generated. In hydrostatic equilibrium this rate q defines the work per unit time of the horizontal pressure gradient, see Eq. (4) in the post. It is given by u∇p, i.e. it is proportional to the horizontal velocity component u_p that is parallel to horizontal pressure gradient.

Thus, Eq. (4) does not constrain the velocity component that is perpendicular to the pressure gradient (e.g., the geostrophic wind). Nor does it separately constrain u_p and the pressure gradient, only their product. In order to find all the velocity components one equation is obviously insufficient. So, while q in (4) is proportional to precipitation P, this equation cannot be interpreted as a kind of rule of thumb “where precipitation is high, wind is strong”. Eq. (4) provides a constraint on the generation of dynamic power, but we certainly need additional information on dynamics as per Euler and N-S equations to solve the problem in full.

After this preambule, I do not think that my replies below will be anywhere surprising.
1. Strongest winds in midlatitudes. Unlike the Hadley cell, the midlatitude circulation cell goes against the gradient of solar power (with the ascent occurring where there is less solar power and hence less potential evaporation). This “forced” cell is heavily impacted by the dynamic processes in the much larger tropical area, with geostrophic winds enhanced by a larger Coriolis force at a higher latitude.
2. there is a sharp drop in wind energy at continent boundaries
3. winds are low above continental areas except over deserts
Surface roughness is higher on land than over the ocean, and is minimal on land in deserts. Note that condensation-driven winds, like any circulation, have an ascending branch (where it rains) and a descending branch (where it is dry). So the existence of winds in deserts per se is not an argument against condensation-driven dynamics.

5. the windiest continent is Antarctica, also the driest.
Antarctica is outstanding not only in being the driest. Unlike in Hadley cell where the ascent and hence precipitation occur over a longer radius (because of low latitude) than the descent, in the polar cells situation is the opposite. So there is an opportunity for the dynamic power that is generated in the midlatitude rain belt of the ascending air to be concentrated over a relatively small area in the area of descent over the poles. Concentration of wind energy produces large local winds over the poles.

An excellent and provocative paper – I do like ideas that make me think!

I couldn’t see where in the equations the effect of suspended (or teminally falling) water droplets on surface pressure was handled. These are the forces exerted on the air by the water droplets suspended in it. I may have missed something, or in the discussion here.

The surface pressure on a patch of ground is the weight of all the material above it, minus its integrated density times acceleration. When water vapour condenses, the water droplets are in freefall, and accelerate downwards. This explains the drop in pressure. Only the air has to be held up by the ground.

But after a few moments the air resistance counters the acceleration, and the droplets reach terminal velocity. The droplets in clouds are supported by the air, which is in turn supported by the ground via air pressure. This implies that suspended droplets contribute to surface air pressure. Only when droplets fall freely, independently of the air, is the pressure reduced.

Thus, I would expect a transitory pressure drop as water vapour condenses and starts to fall, the pressure returns to normal as it reaches terminal velocity, then as the droplet evaporates again the increase in pressure from the expanding water vapour balances the loss of the downward drag forces. What the net effect of all this would require more detailed calculation and more cloud microphysics than I have time for, but my suspicion is that the effect would be less than anticipated based on freefalling droplets.

NIV, same questions that I have, I think this can only be addressed by trying to incorporate these processes in a model and evaluating what happens (on short and long time scales) both with and without these processes.

Note, when I pointed this paper out to Makarieva, she thought the way Bannon handled the falling drops was absolutely wrong. I haven’t looked into it enough to judge, but these are issues that modelers have been ignoring and we can’t tell yet whether all this can be ignored in large-scale weather/climate models

Judy, thank you so much for the opportunity of this discussion at Climate Etc.
Indeed, we find that the derivations presented by Bannon (2005) are incorrect. We have made a detailed analysis of this here. Along the way it turned out that there are related but different inconsistencies in the multi-phase flow treatments outside the atmospheric science domain. E.g. if you read Section 5 in that text, this alternative derivation is incorrect for a reason different from that of Bannon (and this derivation contradicts Bannon’s), but consistent with what is written in multi-phase flow textbooks. There is also controversy between Bannon (2005) and Ooyama (2001). From what we have learnt so far, it looks like it will take some effort to set the record straight now.

“I haven’t looked into it enough to judge, but these are issues that modelers have been ignoring and we can’t tell yet whether all this can be ignored in large-scale weather/climate models”
Our experience has been that there is no sufficient interest in the underlying physics. For example, there are two conflicting derivations of the equation of motion in the presence of droplets, the one of Bannon (2002) (sorry 2005 above was an error) and Ooyama (2001). They directly contradict each other, have different physical meaning. A decade has passed without any analysis having appeared in the meteorological literature that would have addressed the contradiction.

I agree that no reactive motion occurs when droplets start to fall. Initially, when the speed of the droplet is very small and increasing with the acceleration of nearly g it doesn’t have any effect on pressure, later the drag leads to an effect that corresponds to the mass of the droplet when the limiting speed has been reached.

I’m not absolutely sure but I think that the error in Bannon’s paper can be expressed equivalently in a different way as follows:

The two phases that occupy a specific volume at a specific time are not bound together well enough to allow for writing the conservation law of the momentum in that way for a volume that contains both phases. On the contrary each droplet falls independently. They cannot be considered as a body of material as a volume of gas can. The outside pressure on the volume of the gas is not pressure on the droplets. Droplets exit continuously the body at the bottom and enter at the top. They may also be created or destroyed and they may grow or contract within the volume. These processes require handling in a way different from Bannon’s equations.

Agreed, in addition much cloud converts to rain and as the rain hits the ground, the pressure would drop due to reduced mass in the column. The paper neglects to mention any of this process which is likely larger than the one they postulate.

Thank you for your comment. You are right, in the paper there is nothing about droplets. The effect that you are talking about can be theoretically estimated and shown to be insignificant. I can only give you my word on that right now because we still plan to publish it.

But there is another effect associated with the droplets that exists even the droplets experience freefall and do not interact with the air. If we imagine circulation as an elevator — where one part is ascending and another one is descending, we note that the descending mass balances the ascending mass such that the total work of the elevator motor against gravity is zero.
The same with circulating gas: the descending branch serves as a weight for the ascending branch.

Now imagine that we have condensation, which means that some mass ascends as vapor, converts to liquid and falls down in the region of ascent. Our “gas elevator” balance is now broken. There is less gas mass to descend than it has ascended. Thus, the circulation “gas motor” has to do some additional work to push the descending air downwards. This additional work depends on the height from which the droplets are falling in the ascending branch. Incidentally, this work coincides with the amount of frictional dissipation related to precipitation.

This is what we have already investigated and you can read the details here, although the text is not final. In brief under observed conditions the effect does not reduce the circulation power as estimated in (3) by more than 30% (upper limit), but this figure grows with temperature suggesting a suppression of circulation at higher temperatures.

Assuming I’m understanding it correctly, your objection to Bannon isn’t quite what I was talking about. I agree that when the droplets are first formed in freefall, there is no reactive force on the air to balance the weight of the droplets that is causing them to accelerate downwards.

What I had meant, (and what I had assumed Bannon meant although I haven’t parsed the paper in enough detail to tell), was the situation when the droplets have reached terminal velocity – the upward drag force on the droplet has to be balanced by a downward reactive force on the air equal to the weight of the droplets. This adds to surface pressure. I don’t understand how it can be negligible.

It’s Newton’s second law. If the only external forces on the atmospheric (air +droplets) column are the upward surface pressure and it’s weight, then the only way the surface pressure can change is if the atmospheric column accelerates. I agree that initially freefalling droplets do so, that there is no reactive force on the air when they do, and this must lead to a pressure drop. But it only lasts as long as the droplets accelerate downwards. When the droplets are at terminal velocity there’s no longer any acceleration. For the air around the droplets to maintain the pressure drop, it would have to be (net) accelerating downwards instead. Is this the case?

Nullius in Verba, indeed what is discussed in our critique of Bannon (2002) is the reactive motion term, while you are talking about has the form of ρlg term.
Yes, what you are saying about one droplet is correct, but when you translate this to a large scale there are complications.

E.g. you say “The surface pressure on a patch of ground is the weight of all the material above it,”
If there is one droplet above me, what is the area on which its weight is projected on the Earth? I.e. how do you define the size of the patch of ground above which the droplet is? It looks like it is arbitrary, isn’t it.

“Thus, I would expect a transitory pressure drop as water vapour condenses and starts to fall, the pressure returns to normal as it reaches terminal velocity, then as the droplet evaporates again the increase in pressure from the expanding water vapour balances the loss of the downward drag forces. ”
Spengler et al. 2011 (we discuss their work in our ACPD comment here) made an attempt to investigate this for 1-D case. What they found — the pressure at the surface drops immediately upon condensation and never returns to the initial value.

The droplets being accelerated by gravity influence the pressure less by the amount that corresponds to the acceleration by Newton’s law. The reduced pressure influences the rest of the atmosphere and the reduction in pressure is removed trough that. We end up with the same pressure at the surface as without this effect.

What I write above is vague as it does not define, what is the general state of the atmosphere and the surface. Therefore it’s not really possible to make statements like the one I make above.

This is perhaps the most fundamental problem with your paper. You compare columns A and B similarly without well defined environment where they exist. It.s not possible to make statements about horizontal pressure gradients when the overall setting has not been defined.

As I explain in a lengthy comment below, very much that you describe is restatements of common knowledge. Deciding what is different requires well defined description of the overall settings. The described settings must agree on essential points with the real atmosphere.

Now all the strong conclusions are in the air (sic) without clear connection to what happens in the real atmosphere.

“If there is one droplet above me, what is the area on which its weight is projected on the Earth? I.e. how do you define the size of the patch of ground above which the droplet is? It looks like it is arbitrary, isn’t it.”

It would depend on the details of the flow of air around the falling droplet, but there would be a definite answer. The drag-deceleration of the droplet will send out a pressure wave into the air, which when it contacted the surface would constitute the raised surface pressure – the circle of contact would define the pressure footprint.

There are various physical analogies that might be helpful to explore ideas. There is an old scientific riddle about a truck driver carrying a load of birds across a weak bridge. The bridge is strong enough to carry the truck, but not the truck with its load. How does he get across?

The answer usually given is that he bangs on the side to alarm all the birds into flight. With them flying freely, the load is lightened and the truck can cross safely.

But this only applies if the cages are open. If the truck is airtight, the truck will weigh the same with the birds flying or settled, as the downdraft is equal to the bird’s weight.

Another example would be a parachutist in a large, sealed container of air. If his weight was not exerted on the base, one could transport the parachutist and container upward, and then recover the same amount of energy by allowing the container only to descend, giving perpetual motion.

I had a look at the linked document but couldn’t see Spengler’s analysis. Can you be a bit more specific? Thanks.

NIV, and the more obvious example is that we are not flattened every time a plane flies overhead. The key to the hydrostatic assumption is that it only applies when horizontal scales are much larger than vertical scales. A wide enough rain or cloud area would have a hydrostatic loading effect on the surface pressure. Unless the discussion is restricted to wide columns, we can’t consider the hydrostatic pressure to be an accurate approximation.

That particular answer to Held where Spengler is referred to presents basically the standard derivation that leads to moist adiabat. There’s nothing new in that and making the interpretation that they prove the impossibility of condensation in combination to latent heat dominance presents total misunderstanding of the standard theory.

As I have already written twice, everybody agrees that condensation is connected to decreasing temperature. The latent heat dominance does not contradict that. It means only that the rate of cooling is so much less that we end up with moist adiabatic lapse rate that’s typically about half of the dry adiabatic lapse rate.

Whether the effect of falling droplets is significant depends on the time it takes them to fall in comparison to the time it has taken for the air to ascend. If the ratio is very small the influence of the droplets on pressure can be neglected. The same value can be expressed also as ratio of water in droplets to that as vapor.

In other ways precipitation is certainly important. One interesting question is to what extent they fall in the rising column and to what extent the end up outside that in drier air where evaporation occurs rapidly and changes the properties of adjoining air.

Precipitation efficiency, which is the ratio of surface precipitation to column condensation, is an important parameter in determining hurricane intensity, and it is the surface pressure effect that is at the center of this. There have been papers on this issue. This efficiency is a function of microphysical processes affecting the rain production rate.

I have to admit that I hadn’t gone trough the whole article before writing my earlier comments (and I’m not totally trough even now but far enough for what follows). Going trough the paper does not explain to me why it has been written as it has, and going trough the paper raises questions on why the authors write, what they write. They seem to be implying that their statements would provide some essential new insight where I don’t see anything new.

The mathematical derivations start in Chapter 2.1. There they present a derivation that must be essentially the same as that used in textbooks to derive the moist adiabatic lapse rate (I haven’t worked out the details). They don’t go trough all the steps to the lapse rate, but what they do is included in that derivation.

They end the chapter “This proves that water vapor condensation in any adiabatic process is necessarily accompanied by reduced air pressure.” That’s essentially equivalent to the well known fact that adiabatic condensation occurs always in ascending convection where the parcel of air moves to lower pressure and cools. Thus the observation is really well known.

Next they put the sentence “Adiabatic condensation cannot occur at constant volume” as the title of the next chapter. That chapter contains only an obvious corollary of the previous one. Again very well known.

Next chapter on non-adiabatic condensation tells also only very well known facts.

In Chapter 3 they derive the barymetric formula for dry and moist profiles (nothing exciting here). The main differences are due to the very different lapse rate that makes the density of the moist profile fall faster than that of the dry profile. (With increasing altitude the pressure drops and that makes the density go down, but the temperature drops also and that has the opposite effect making the decrease in density with altitude the weaker the larger the lapse rate is.)

Adding the influence of water vapor concentration to the density profile makes the difference between the densities of the two cases a little larger, because water vapor lowers the density as H2O molecules are lighter than average for dry air. The main deviation in the density profiles is still due to the difference in the lapse rate. The lapse rate effect is discussed in every textbook on the subject, the small additional effect due to changing water vapor concentration not. To get the order of magnitude lets assume that the vapor pressure at the surface is 30 mbar. That reduces the density by 1.2% in comparison with dry air. At the altitude of 5 km the saturation pressure could be 7 mbar and its influence on density 0.3%. Thus we have an effect of 0.9% in the density.

At the altitude of 5 km the pressure is a little more than 500 mb with a little influence from the temperature profile and much less from the moisture profile. The temperature would be almost 50 C less than at the surface based on the dry adiabatic lapse rate and roughly 25 C less based on moist adiabat. Thus we find about 10% difference in the density as the first order effect.

The density of the moist atmosphere is lower at the surface and the difference grows with altitude as the moist atmosphere is warmer. Above the altitude of about 0.5 km the difference in lapse rate is the main reason for the density difference. As the moist column has a lesser density, it’s pressure drops more slowly with altitude.

The differences in moist and dry columns are essential foe many weather phenomenons. Everybody is likely to agree on that. My understanding is that the only point that the paper tries to make is that the influence of water vapor content on the density of air has not been taken into account in all calculations. Further they imply that its influence would be a major one. I cannot see, how that could be the case taking into account also that this effect weakens with increasing altitude.

How they reach such conclusions from the changes described above is another question. My view is that they don’t give sufficient emphasis on discussing the physics but perform calculations that are not really applicable for the physical case. Such calculation may get spurious strong results by applying some unphysical constraints, which exclude natural processes that occur in vertical direction and are therefore forced to introduce excessively strong effects horizontally. It’s possible that they use altitude as vertical coordinate in a situation where geopotential height would be more appropriate. I have not tried to figure out, whether this is the reason.

When you get to such small impacts,just about any approximation can lead to spurious results. Consider geopotential height, fine for weather, but for climate 50 meters of sea level change is nearly a half degree of error trying to estimate a 1 degree impact. So if you use geopotential height, what baseline do you select?

Then as snow line and glaciers retreat, the moist air envelope would expand changing the virtual temperature and the CAPE in the higher latitudes, SSW events?

Most of the controversial parts of the paper are in the manipulations following Eq 34. A major mathematical fallacy is responsible for these.

Eqs 32 and 33 are conventional conservation of mass equations. Eq 34 looks like a consequence, but has been formed by a first principles argument involving reference volumes. This is just another way of doing cons mass, and should yield the same result. There is a slight error. In the correction -Nv/N (&partial;N/&partial;z) she uses ordinary air (N) as the non-condensable reference. But it isn’t, quite. She should have used Nd, dry air, and then the equations would be entirely consistent. But they are close.

The major math fallacy is that she proceeds with the algebra as if the different mass conservation equations are independently true. This introduces a new equation to the effect that the discrepancy is exactly zero. All sorts of things can follow from that.

The analogy I use is, suppose you have a derivation that yields x=1, and another that yields x=0.99. For many purposes, that is not a problem. But if you insist that both are true, then you can subtract (0.01=0), multiply by 100 (1=0), multiply by the national debt – well, you get the idea.

I continue to claim that the errors originate in not defining the overall settings. There are equations but their relationship with the full problem are not well defined. Therefore additional assumptions are needed and these assumptions but these assumptions are not formulated explicitly.

Another point was the reply to Held’s comment the Makarieva linked to in one of her most recent comments. That was a pure strawman argument based apparently on misinterpreting standard thinking.

I try to be a little more specific of the issue where I see the problem.

In order to discuss horizontal pressure gradients a plausible overall setting is needed. Looking at two columns (moist and dry) tells only that they are so different that they cannot coexist in the same atmosphere without much more that must be taken into account.

We have here the comments of Roger Pielke Sr along the same lines telling that a variety of mechanisms is always triggered by a combination of such columns. Horizontal winds related to the columns cannot be restricted to them alone. Taking the removal of water vapor from the air into account does not create any fundamentally different situation, it only changes a little the quantitative details. By far most of the structure results from the very different lapse rates which are determined mainly by “the dominance of latent heat release” as Held put it.

The paper may present something that changes a little the quantitative details, it does not present any new overall mechanism to tell “Where the winds come from”.

Most of the controversial parts of the paper are in the manipulations following Eq 34. A major mathematical fallacy is responsible for these.

I think that it might be productive for you to decide whether you want to persuade your readers in a mathematical or a physical fallacy present in our paper. It is easy to see that you cannot have both, so this takes away from the strength of your critique. This seems to be a persistent uncertainty. E.g. while you started your comments to our paper as “Mathematical doubts”, you ended them with (my emphasis) “I still can’t see the basis for Eq 34, and in particular what extra physics makes it independent of Eqs 32 and 33.”

For example, you now say that the fallacy is mathematical. However, anyone able to perform basic algebraic operations can see at once that all the equations in our paper are mathematically consistent. Condensation rate S in the continuity equations (32)-(33) is undefined. It is an unknown function. So in order to gain anything from the continuity equation, one needs to specify S. This is done in Equation (34). If you are concerned about mathematics, you can formally take Eq. (34) as a postulate. From this postulate and the continuity equation you then unambiguously obtain Eq. (37), which is the main result. I am sure that you will not be defending the statement that Eq. (34) can be mathematically derived from the continuity equation.

So, I suggest that you should instead insist that our paper contains a physical fallacy. It is more logically consistent. You should say that the assumptions that we involve to justify Eq. (34) are not convincing or anything obvious to you. To this I will respond that to us those physical assumptions do seem plausible. Moreover, I will say that there is a totally independent set of physical considerations that give the same result (Eq. 37) without involving the continuity equation at all (like Eqs. (1)-(4) in the post, see also the unnumbered expression for f_C on p. 1044). I will also say that the obtained result agrees with observations. At this point I think we will need to leave the readers of the paper to think for themselves not being able to add anything significant.

I should perhaps add that your case would be stronger if you not only be saying that our assumptions behind Eq. (34) are not convincing or following from nowhere, but rather showed that they violate some well-established physical evidence or equation or, even better, gave an alternative expression for condensation rate S.

Nick, let me consider your point about this mysterious small magnitude in somewhat greater detail.

The analogy I use is, suppose you have a derivation that yields x=1, and another that yields x=0.99. For many purposes, that is not a problem. But if you insist that both are true, then you can subtract (0.01=0), multiply by 100 (1=0), multiply by the national debt – well, you get the idea.

It might be a vivid picture but to make it relevant you might need to give your readers some specific details: how does it actually pertain to our work, if at all? What is this small magnitude that you are talking about?

In the meantime, let me present our take on this small magnitude issue. It is in fact very interesting even if unrelated to our main conclusions.

In a horizontally isothermal atmosphere with ∂Nv/∂x = 0, the continuity equations (32)-(33), where S still remains an unknown function and no Eq. (34) is in sight, can be re-written as follows (see Eq. (6) in the post and (A7) on p. 1053 in the paper):
-u∂N/∂x = (S – S_d)/γ_d.
Here S, I emphasize, is an unknown function and S_d is expressed as the vertical derivative of the dry air relative partial pressure γ_d ≡ p_d/p, and N is molar density of air. There are two points here: first, that γ_d is very small and second, that S_d captures the main terms in the condensation rate, so S and S_d are very close whatever S is. (The ultimate reason for that is that the vertical pressure gradients are much larger than horizontal pressure gradients.)

Owing to the ideal gas law p = NRT, ∂N/∂x is proportional to the horizontal pressure gradient. So what we can learn from the above equation is that the horizontal pressure gradient is a function of two close magnitudes divided by a very small magnitude. So if we derive S from some independent considerations, we will need to ensure a very high precision of those considerations, to be able to have an accurate estimate of the pressure gradient. As we argue in the post, the first law of thermodynamics that is present in the standard set of equations solved in the current models, cannot provide the needed precision because of inherent physical limitations. This is the reason why, in our view, the condensation-induced dynamics has not been systematically studied or previously described from a theoretical viewpoint.

Note that all the above reasoning does not involve any assumptions about condensation rate S. It is generally valid.

“I think that it might be productive for you to decide whether you want to persuade your readers in a mathematical or a physical fallacy present in our paper. It is easy to see that you cannot have both, so this takes away from the strength of your critique.”
Not at all. The physics fallacy is believing the new equation (34) is based on physics other than mass conservation. You have often claimed that, but never said what that other physics is.

But the math fallacy is then using it as an independent equation. You already have sufficient equations in Eq 32 and 33. Eq 33 determines S. You then add Eq 34 as another equation in the same variables as 32 and 33. The system is overdetermined.

Proceeding from there just leads to nonsense results. For example, I noted that if you combine Eq 34 with 36, you get S=u∂N/∂z. That is, precipitation rate is equal to a wind velocity component times an air density gradient. This doesn’t require the presence of water at all. Rain out of dry air!

In terms of mysteries, we now have another one. You now say that
u∂N/∂z=-(S-S_d)/γ_d. That is a different expression again from that yielded by 34 and 36. That is the problem when you force solution of an overdetermined system. You can get anything.

In terms of mysteries, we now have another one. You now say that u∂N/∂z=-(S-S_d)/γ_d. cThat is the problem when you force solution of an overdetermined system. You can get anything.

Nick, why not to perform elementary algebra first? You have now announced another mystery, but try to put Eq. (34) into the equation above and you will get (37). Or you get (37) from (34) and (36). They are all consistent.

So your claim
“That is a different expression again from that yielded by 34 and 36.”
is incorrect.

I’ll reply to the rest of your comments a little later. Thank you again for rasing these issues here.

(I missed the start of this very interesting (in hindsight) thread by three days so it’s taking me a while to get caught up with the earlier comments.)

@PP: “This proves that water vapor condensation in any adiabatic process is necessarily accompanied by reduced air pressure.” That’s essentially equivalent to the well known fact that adiabatic condensation occurs always in ascending convection where the parcel of air moves to lower pressure and cools. Thus the observation is really well known.

1. I would accept your rephrasing if stated as “adiabatically risingmoist air eventually results in condensation.”

Obviously there can be no condensation with dry air. Moreover condensation is not a result of decreasing pressure (quite the opposite in fact) but of decreasing temperature. Relative humidity decreases with isothermally decreasing pressure, but not as fast as it increases with decreasing temperature when both are the result of increasing altitude. It’s therefore the rising that’s important.

2. I would not however accept that this rephrasing is equivalent to AM’s phrasing “water vapor condensation in any adiabatic process is necessarily accompanied by reduced air pressure” because the latter carries with it the implication that if significant condensation occurs at a fixed altitude, with no other effect such as failling rain, then there is a reduction of air pressure. This can’t be the case for the obvious reason that pressure is determined solely by the mass of air and water above it, which is unchanged by condensation. Instead condensation can only occur as a result of decreasing temperature and/or increasing pressure, with temperature trumping pressure when both are decreasing due to altitude.

When the condensate starts falling is another matter, but that’s separate from condensation itself, which is all that the analysis of sections 2 and 3 of the paper treat.

3. Nothing has been said about the rate at which condensation occurs, however caused. Even if it had been the case that condensation reduced pressure, this change in pressure could in principle be so slow that its contribution to wind would be negligible compared to the other influences.

I don’t see any problem with the rest of this long comment of Pekka’s, but it was an early comment anyway and superseded by his later comments after reading more of the paper.

“Instead condensation can only occur as a result of decreasing temperature and/or increasing pressure, with temperature trumping pressure when both are decreasing due to altitude.”

This is wrong. Air containing water vapor, cooled to (and under) its dew point, will not undergo homogenous condensation (supersaturation). Only condensation nuclei (ions, hygroscopic condensation nuclei…) will induce condensation.

Hi Anastassia – Thank you for your reply. The fundamental issue that I disagree with you on is perhaps captured by your statement that

“all the derivations are made assuming that the hydrostatic equilibrium is exact.

This is indeed the issue. Accelerations do occur even in a hydrostatic system. So do dynamic pressures. This is what causes the rapid adjustment to the pressure field when density changes, such as when condenstation occurs.

I just want to congratulate our hostess for putting such a challenging paper on this blog. Having read some of the commenters posts for a couple of years now on hundreds of topics, it is evident that this paper has really stretched them all. Science has to be the winner from all this.

I think most commenters need to take a much better look at this problem before unloading, including some of the original reviewers. The main problem, I think is that Anastassia and her colleagues have done a lot of thinking about this already and have a hard time now reconnecting with the rest of us, although they are doing a lot of effort. I think it would help a lot if some people who are now very critical do an effort as well, because most of the criticism is, I am sorry to say, superficial. You really need to try to do some of your own sample problems besides the ones given in the paper. So far, i have not really found anything that goes against conventional physics although I would readily admit I am not an expert in this area. And about these comments about “providing code”: what else could it be to it then to do exact bookkeeping of water in the gas and liquid phases in weather prediction models and use that to calculate or correct the hydrostatic component of pressure?

Cees de Valk says “I think most commenters need to take a much better look at this problem before unloading, including some of the original reviewers. The main problem, I think is that Anastassia and her colleagues have done a lot of thinking about this already and have a hard time now reconnecting with the rest of us, although they are doing a lot of effort.”

Precisely the same could be said of the folks at Principia Scientific International (PSI), eh?

‘Prediction (the Zeroth Law of Thermodynamics) It is a remarkable mathematical theorem, that although the mass density and the energy density both will be found (in general) to be strongly -dependent, the temperature so (numerically!) computed will be found to be independent of , which is physically to say, the temperature of a fluid column in a gravitational gradient is constant throughout the column.’

Write the code Kyuna – I am assured that such goobledegook will follow the age old princple of GIGO to the nth degree.

The way the comments are presented reflects the grandiose claims of the title of the paper. Writing such a title brings attention, and largely critical attention when the paper cannot provide solid support for the title.

It is called a theory ,or an alternative explanation of the problematic area in hydrodynamics such as hydrostatics which deals with the Euler and NS solutions (with all their accompanying problems) and where solutions to the hydrostatics are indeed very rare,and great care is needed,

The arguments that the existing theory is complete or correct is naive at best.

The problem is this. folks have asked questions repeatedly starting at the air vent, then at lucias, and finally as reviewers. Folks who have worked their whole lives in modeling just these sorts of processes. Some folks well recognized in the field. Getting aswers to these questions would allow testing to proceed. without those answers nothing can be done. yet the authors refuse to clarify. They are wasting the time of smart people.

And in the midst of this they trash the work of authors who do supply working equations and they feed the doubts of the uninformed.

I think, Steven, that you are exaggerating. Wasting the time of smart people? As Nick Stokes mentioned here the other day, “There is essentially no mathematical defence of the work by anyone other than Dr M.” But equally there is essentially no mathematical attack on our work by anyone other than Nick Stokes. He is actually doing all the job for those smart people who want to be critical. But it looks like (and I hope that) Nick does not mind, so all is well.
Besides, many people enjoy intense discussions like this one, so I think that many smart people do follow — even if for fun. It is like watching boxing, you know. But unlike in boxing, where everyone understands what the two men are actually doing, here there is an additional bonus for the smart: the more you understand the specifics of what is going on, the more you enjoy.

I agree Dr. M. This is a fascinating discussion and quite typical for bold new ideas. Mosher is just using stupid meta-arguments, which he is fond of. I look forward to further research which is all that is needed. Hang tough in the face of empty criticism.

This is the first I’ve heard of any of this, even the post let alone the paper it claims to defend against its critics. The following is therefore to be taken with several grains of salt.

From a quick read of the post I gathered that the paper starts from sound microphysics and passes to what looks to me like unsound macrophysics.

The microphysics is that when a water vapor molecule condenses on a water droplet, its translational energy, aka its latent heat, is converted to sensible or thermal energy, which the droplet then distributes democratically to all its constituent molecules.

This much is fine.

The authors infer from this the macrophysical claim that condensation drives temperature upwards.

Arrgh. This is rubbish. (Feel free to interpret “this” as referring to the previous paragraph or this one. Choosing the latter will save you having to read the rest of this comment.)

Transitions between the solid, liquid, and vapor phases of typical substances, water being no exception, are completely reversible. Le Chatelier’s Principle (as applied generally to physical as well as chemical processes) therefore holds. For any circumstances (in particular temperature) there is an equilibrium between phases.

Equilibrium is standardly analyzed in terms of constituent proportions (in this case the two phases of water as respectively molecules and droplets sparsely populating air) and temperature. In equilibrium at a fixed temperature water molecules pass between their vapor and liquid phases in equal numbers. With decreasing temperature the equilibrium shifts to favor the liquid phase (with the caveat that the process can be very slow due to the empirically observed tendency of vapor molecules to bounce off droplets when intuition would suggest they would stick at first hit).

A complicating factor with Le Chatelier’s Principle is the notion of an exothermic reaction. For example 2H2 + O2 converts to 2H2O exothermically, a positive feedback that hastens the reaction so as to drive it rapidly away from equilibrium (witness the Hindenberg).

Likewise the assimilation of a free-range water vapor molecule into a water droplet is also exothermic. This is because the droplet converts the translational energy of the captured vapor molecule (close to Mach 1) into thermal energy, much as a meteor (way more than Mach 1) burns up in the atmosphere, or your disc brakes get hot bringing your car (definitely not Mach 1) to a halt.

But there’s a difference from the Hindbenberg: the feedback is negative. This is because increasing temperature promotes evaporation of the droplet, which quickly restores equilibrium.

When the feedback is negative like this, the temperature is not merely the dominant driver, it is the only driver.

This CE post proposes to respond to what the authors claim to be the three principal criticisms of the paper, namely that the extant models are sufficiently (i) comprehensive, (ii) effective, and (iii) comprehensive as to gain nothing new from this paper.

My criticism is none of the above. It is simply that condensation does not drive temperature in the manner envisaged in the paper at all. Rather the temperature of the atmosphere governs the rate at which condensation occurs. The bottom of a cloud is the altitude at which the temperature is low enough for the equilibrium to shift to the point where droplets become visible.

Those saying that the impact of condensation on temperature is small enough to be negligible could more accurately say that there is no impact at all. Condensation simply is not a driver.

From the perspective of Le Chatelier’s Principle, clouds happen at the whim of temperature (which in turn is governed by altitude), not conversely.

Much of this discussion has been about theory. Our paper and our blog were about theory too – so that makes sense. But I suspect many readers are interested in evidence. Dr Held too asked for “evidence” to pass his “high bar” – we rejected the argument as a point of principle. The question at issue then was whether we had presented a case coherent and interesting enough to answer: it is a theory. Theories come first the evidence comes later.

But that does not mean we don’t have extraordinary evidence.

We wrote a little about this in the paper (most points below can be explored by looking at the reference list there or at http://www.biotic-regulation.pl.ru/index.html), but it may be useful to highlight a few again here so you can make your own assessments. What is our evidence so far? How does out theory match reality?

For me the most powerful evidence comes from looking at how rainfall varies as we travel inland from the coast (over relatively flat terrain): Why does rainfall not decline over forest? It declines over non-forest in a relatively constant manner that is easy to understand (This seems to be a global pattern: see the figure in my previous blog here http://judithcurry.com/2011/03/30/water-vapor-mischief-part-ii/). Recycling is not an explanation – it would reduce the rate of decline but it could not prevent it. There is no alternative explanation at present.

This effect – the drawing of rain into continental interiors – requires a biologically functioning forest so we would predict that the effect will be smaller over boreal forests in deep winter (when the forests are metabolically inactive and not transpiring moisture). Observations support these predictions. There is no alternative explanation at present. See, e.g. Makarieva, A. M., Gorshkov, V. G., and Li, B.-L.: Precipitation on land versus distance from the ocean: evidence for a forest pump of atmospheric moisture, Ecol. Complex., 6, 302–307, 2009.

Our paper (discussed in this post) shows that we can estimate the power of global atmospheric circulation. This is the first ever such estimate developed from first principles and, though intended as a rough estimate, is remarkably close to the measured values. No alternative theory can currently explain this value.

Where we have good data on forest loss and rainfall change there are some observations suggesting a regional decline in rain regularity (as we would predict). See E.g. Webb TJ, et al. 2005. Forest cover-rainfall relationships in a biodiversity hotspot: The Atlantic Forest of Brazil. Ecological Applications 15: 1968–1983.

The work by Anastassia and co. (not me!) on hurricanes is also impressive: it shows that the condensation generated pressure gradients can give a physically and analytically consistent model of how such storm systems function and can be used to estimate several characteristics from first principles. E.g. Makarieva, A. M. and Gorshkov, V. G.: Condensation-induced kinematics and dynamics of cyclones, hurricanes and tornadoes, Phys. Lett. A, 373, 4201–4205, 2009.

So the score-card so far is 7:nil in favour of our theory (I rate the hurricane work as three points … but even if you don’t 5:nil is a good margin). That’s a good score line. Extraordinary? Well I acknowledge too that the search for counter-evidence is in its infancy.

So now the theory can and should be tested further. All those who think it is right, all those who think it is wrong and all those who are uncertain but recognise why it matters, can I hope agree that the ideas should be tested. That is a common goal.

@DiA: So the score-card so far is 7:nil in favour of our theory (I rate the hurricane work as three points … but even if you don’t 5:nil is a good margin)

Regardless of the margin, let 7:nil = x and 5:nil = y. Then 7 = x*nil = nil = y*nil = 5. Subtract 3 from both sides to give 4 = 2 and then divide both sides by 2 to give 2 = 1. Since you and Tony Abbott are two, you and Tony Abbott are one. No surprise there.

More seriously your theory takes various correlations and claims causality for them while ignoring that correlation is not causality.

Fun thanks
Indeed correlation is not causation. The process here is about falisification.
Any theory that can explain a phenomenon lacking previous explanation or can predict an observation (or correlation) that other theories cannot certainly looks better than one that fails to so.
Indeed some science philosophers think the whole point of the science process is about finding theories and then finding data (results or observations) that could potentially falsify the theory. The point is here that the data collected support rather than contradict the theory and the score-card is in our favour. If we get into more detail that may change. There may also be alternative explanations for some of these observations … so I accept there is a need to go much further if we can,

Indeed Douglas, where causation is plausible correlation is evidence of causation. So you in fact have some evidence. You have an evidence based conjecture and that is how science progresses. What is interesting is that people want to reject this conjecture for no reason except that it is such. Your answers are very good. Some of your critics seem to claim that conjectures should not even be published! They are very wrong.

They got their theory published, doc. While you will be back at the AGU next year with the same little ole quasi-poster with the big red letters and the big red arrow. Will you take willie with you, to hold your poster?

Mosher has an in with COMICS. I bet he could get them to start a Deep Earthquake Science for Dummies journal for you. (Now let’s see what willie the yapping, sniffing stalker does, if he is not too busy sniffing and yapping at doc Douglas.)

Now, we need a quote showing that “some science philosophers think the whole point of the science process is about finding theories and then finding data (results or observations) that could potentially falsify the theory.” You might have a tough time, since Popper’s claim was prescriptive, not descriptive.

The other day, it was Feynman and Einstein. Now, it’s Popper. You do seem to have all your talking points prepared for your entrance, Douglas.

***

Speaking of which, tallbloke’s, via the GWFP, both reproduced this interview with The Australian:

HI Willard
Thanks for the continued interest
Sorry … I sincerely thought that the “no” answer would be self evident. (That article is not what this thread is about. Too many tangents and possible distractions (over 500 comments already) I can appreciate the flippant and theatrical ones without responding to each). Right now the most constructive action appears to be on other threads (Anastassia and Nick) — let’s enjoy it.

MIchael – “How …”
Its in the first blog link in the blog text above (climate etc.): I wanted to know if these ideas were true or not. I received diverse responses … but I also realised that they were not getting a fair hearing (scientifically reasoned). Well we’ve made progress.

Michael “The question remains”
Sorry I don’t grasp your point. You know my motivation and you know I offered to provide help and have done so. What else do you need to know? I have a natural sciences background so dont find the math as scary as some though most certainly I lack the quick precision insight of Anastassia and Victor. I think for this theory there is a an advantage in coming from outside the discipline and not being weighed down by the implicit assumptions etc. What is your interest in this? Or rather why do you think the question is relevent here?

Willard
I fail to grasp your point (though yes I do appear to be allowing myself to be distracted despite myself … also a proposal deadline so nothing persona if I am tersel).
You do or you dont think a discussion of our evidence and how me might be able to falsify or find support for our theory would be useful? Clearly I would. I hear quibbles and side-tracks but not susbtance. Entertaining certainly, but unsatisfying. If you could get the cryptic and snide stuff under contriol we might even manage a constructive and substantive conversation. Not sure that’s what you want but I’ll keep an open mind.

There’s just such a jump from your usual publication topics (very interesting) to this.

And yes, plenty of people are capable of the maths, but as has been pointed out a few times on the thread, a deeper understanding of the topic (atmospheric physics) is helpful in avoiding descent into mathematically correct physical nonsense, or excited claims for newness of what is already well known by specialists in the field.

Michael “a deeper understanding of the topic (atmospheric physics) is helpful”
I agree … which is why we sought to do this (open paper, blogs etc). Despite all the suspicions — apparently many — we want to know if this idea is true. That’s it. That’s why we are here. We hope to engage persuade or be persuaded.

My point is that the consequences of the results in your paper, e.g. the correctness of actual atmospheric models, might be more fruitful that discussing the principle of falsifiability. To be able to falsify a claim is welcome, but it’s not an absolute.

There, I’ve said “absolute”. I’m sure you agree.

***

I could tell you about the need to naturalize epistemology and that holism wins in the end, but I’d rather not. I also surmise that that you’re not the substance guy. So if I ever want to discuss substance, I’ll contact Anastassia or Antonio.

Sorry everyone:
Pasted the wrong citation for the seasonal evidence of point two in my list (the effect is predicted to require a transpiring forest). I meant this one:
Makarieva, A. M., Gorshkov, V. G., and Li, B.-L.: Revisiting forest impact on atmospheric water vapor transport and precipitation, Theor. Appl. Climatol., 111, 79–96, doi:10.1007/s00704-012-0643-9, 2013.
its worth a look if you can access it.
[The one I had pasted belongs with point one (the relation with annual rainfall)]
Apologies for the confusion

While that’s easy for you to say it does not agree with the journal’s statement: “The handling editor (and the executive committee) concluded to allow final publication of the manuscript in ACP in order to facilitate further development of the presented arguments, which may lead to disproof or validation by the scientific community.” [Emphasis mine]

The theory is published: now we need disproof or validation.

Sorry if that was news to you, I’m just the messenger in this case. (Full disclosure: I believe this article will go the way of cold fusion, the OPERA neutrino faster-than-light anomaly, and the retroviral theory of chronic fatigue, but faster since it’s more obviously wrong.)

Vaughan Pratt “it does not agree with the journal’s statement”
Indeed. It wasn’t meant to — I do not speak for the journal. I was calling people’s attention to the idea of evidence as an alternative means to advance this theory. Having more people aware of the evidence we have (whatever they think of it) can encourage scrutiny and further work from those interested.
Does it need repeating that I concede the possibilty of a logical or analytical error (I’ve asked for that type of scrutiny many times from all kinds of people so thats on the record … indeed that is why we are here now)?
As I keep repeating too the skeptics (those willing to do the hard work, not the Moshers and Willards etc.) are actually our biggest resource here. You may be correct (a quick disproof). Let’s see. If so I shall be a little dissapointed but will be glad for the final resolution.That’s how it works right?
After so many years in public review I was less convinced that a knock-out blow is likely. If not how shall we progress? There may be readers here who find the idea of evidence interesting. That’s my hope.

Does it need repeating that I concede the possibilty of a logical or analytical error (I’ve asked for that type of scrutiny many times from all kinds of people so thats on the record … indeed that is why we are here now)?

Your paper has an interesting history. As far as close scrutiny goes, four out of five referees recommended rejection in 2009, on grounds that make complete sense to at least some of us here. Yet “here we are now” as you say, rehashing all the same objections. Perhaps the true destiny of your paper is as the Flying Dutchman of atmospheric physics.

(Incidentally I knew a Beau Sheil in Sydney in the 1960’s, we were residents of International House, and two decades later lived near each other at Stanford. Any connection?)

Vaughan Pratt “four out of five referees recommended rejection in 2009″
Thanks for the interest
I think it was one out of two (i.e. invited referees). You can check if you like. Its not so unusual with peer review — though I think noone would have objected if they had then sought a third reviewer.
A point that has not come up yet is how Dr Held was identified and invited as a reviewer. We actually helped do that ourselves in the full knowledge that he would be critical — that likely also affected the journal’s assessment. (If you get a submitted paper critical of a given theory you would, if you are an editor, send it to one opponent [someone directly criticised] and one less involved and see how each judges the work and then weigh the justifications offered accordingly). In any case the referees points were addressed. Despite the various claims repeated the paper changed quite a lot. The appendix for example was added.

“all the same objections”
No I think we have progressed. The scrutiny may ultimately leave both sides slightly unsatisfied but I do see clarification concerning what the core issues are (that is the way the system works formally). We have gone beyond saying Eq 34 is simply “wrong” to assessing what it implies and how it might be tested.

(Beau? I will check … I do have relatives in the country but have not heard of him, its not a very common surname so I would guess some connection. I’m not Australian myself)

@DiA: (quoting me) “four out of five referees recommended rejection in 2009″ Thanks for the interest. I think it was one out of two (i.e. invited referees).

Sorry, my mistake, the “rejection in 2009″ was of the hurricanes paper Rosenfeld was critiquing, which only had Makarieva, Gorshkov (VG) and Li as authors — you and Nobre joined the “condensation reduces pressure” team when “hurricanes” were reduced to “winds”. I see now it’s up to six with the addition of Peter Bunyard in further reducing “winds” to “air passage” (last on the list below).

Most of the following papers invoke condensation as a mechanism, especially as one that reduces pressure. They also include refutations of arguments based on one or another violation of some thermodynamic. Given the generally negative reviews of the more recent of these, sorting out which of these mechanisms and refutations the referees are generally comfortable with seems like a nontrivial task.

Michael
Well we know its controversial.
See this earlier link for the key Meesters et al. texts and the reply: http://judithcurry.com/2013/01/31/condensation-driven-winds-an-update-new-version/#comment-291430
Meesters and colleagues did a valuable service in addressing the ideas in a formal manner. I wish they would do more. (The article in your link is in large part derived from Daniel and my article but re-jigged to highlight the formal Meester’s et al. review. There was then a response and a reply I think).

VP Perhaps the true destiny of your paper is as the Flying Dutchman of atmospheric physics..

DM Or perhaps it will become a perennial poster at the annual AGU meeting. A recurring unphysical bad penny.

You mean like the perennial models of Pratt,who keeps moving from statistical artifact (such as the AMO) to statistical artifact (blowing his harmonics) when wind instruments are not possible in Flatland eg (Abbot 1899,)

‘A point which has been increasingly emphasized in M&G’s successive expositions of the biotic pump theory, is the “pressure drop” which occurs on condensation. Since condensation implies disappearance of water molecules from the vapor phase, there remain indeed less molecules which exert pressure. But on the other hand, condensation heats the air parcel and hence causes faster molecular motion and a rise in pressure, which is neglected in the calculations of M&G. Actually, condensation causes not a drop but a rise in local pressure (compared to parcels at the same height but without condensation). This is accompanied with expansion and thinning, contributing to the well-known buoyancy of convective clouds. This mechanism of heating and expansion is a fact which has been very well observed, and it strongly contrasts with the one proposed by M&G in which condensation is regarded as the cause of an ongoing implosion.’

It is not clear how much of the heat that appears in water droplets is lost radiatively or kinetically in heating the surrounding air parcel. Does this heat rise and expand in these types of clouds. It appears so looking at cloud time lapse photogtaphy – but again it is not clear why in an unconfined volume that a temperature increase should cause an increase in pressure and not an incease in volume – indeed as stated in the excerpt quoted.

Contrary to the claims of the blogosphere – it seems again that no fundamental problem has been identified. This is an ‘error’ identified by Pratt and Rabbett below – but not one that holds any condensation.

What happens in condensation is not mysterious or unknown to the least. How pressure and volume react locally is not an open question.

The larger scale conditions vary and consequently the resulting weather phenomena vary, but that’s a problem on the next level. The idea of pressure drop as described in the present or related papers is simply totally wrong. That’s not proven by studying these papers beyond the observations that their argument lacks all valid basis and is based on explicitly erroneous reasoning. That their conclusion is wrong is shown by the standard calculations that take all physical phenomena routinely into account and don’t miss anything in contradiction of the claims of the authors.

That a few people make baseless claims is of zero value, when they cannot justify these claims and when these claims lead to some strong results that are totally erroneous by contradicting very well j´known facts.

It’s always good that people try to find new ideas, kudos on that to the authors, but it’s not good to be stubborn when errors in reasoning have been proven. Yes, they have been proven. That there are people on this blog who cannot follow the proofs does not weaken the proofs.

Nothing can be proven in physics to people who accept only what they understand but who don’t understand any physics.

@DM: Or perhaps it will become a perennial poster at the annual AGU meeting. A recurring unphysical bad penny.

This Monfort character (if that’s his True Name) seems to have taken a distinct disliking to me. This raises the fascinating question of how many beers I’d have to buy him to make him any friendlier.

If his ideology forbids befriending the mathematically competent I’d guess the answer would be enough for him to pass out on the floor, for which his wife would then blame me. So goes modern environmental science.

Steven Mosher
If you are so certain it is wrong please take a little time to get specific as to why (as Nick has). We vould all value that. Your criticisms so far lack any technical substance. They are based on fasle claims or repetition of other people’s comments that were answered already. (I admit I like your unicorns — humour is always welcome).

Mosh’s unicorn example is a technical comment, if you consider epistemology as a technical field, which you should. It underlines the need for a mechanism.

Not only your theory needs coherence, but it needs to posit causal relationships that could make sense in the overall theories covering yours. If we have the choice between maintaining the overall picture we have of the climate and trying to decipher a paper where there is the vague promise to overthrow AGW, the choice won’t be tough to make. Just as it ignores iron suns, it’s the sun stupid, and the like.

In principle, some might try to falsify your claim. But void of specific mechanism, the threat for now.

And all that assuming that the formalities are correct, when you have people telling you they’re barely coherent. So even on the formal front, nothing is won yet, at least as far as scientific acceptance goes.

Perhaps you could ask Dr. Monkton to join his tour? Your presentation would make a nice first part.

Knowing “the” mechanism is nice. Sometimes though you have to better describe the phenomena before you can determine “the” or combination of mechanisms required to explain all the details causing the phenomena. Their “new” idea is easy to evaluate, does it improve the predictability of cloud formation and precipitation?

I mean, having absolutely no clue how clouds respond to just about anything didn’t hold back Hansen :)

Willard, without PR you are lost in the noise. It is far than “it’s the forest stupid” though, more like its the water stupid, we live on a water world :)

Did you know that for every degree of surface warming the average cloud base height would decrease? I believe that is a negative feedback.

Forests though, which were closed to wiped out near any growing city state back in the day though, would have had some significant “local” impact. But if you look at the dark albedo of those forest from space, you would assume that they have a warming impact. I imagine that if it weren’t for the hydrology cycle they might, but then they would be dead wouldn’t they?

Hey, BC, did you know that rain follows the dance? People don’t enjoy dancing in the mud, they prefer to wait until the ground has thoroughly dried out. However there’s a higher probability of rain following a long dry spell than a short one. So after a while people started to notice that rain follows the dance, giving rise to rain dances as a way to encourage rain.

What’s more it worked, as long as you refrained from dancing in the mud.

Tell it to Glastonbury – which reminded me of the Glastonbury Romance – a wonderful modern retelling of the Grail myth by John Cowper-Powys’s. There are seven stations in the Grail vision. The first is a shining fish – and a question asked. The question asked was ‘is it a tench?’ The seventh Grail vision portends floods and cataclysms. I have a bit of a history of vividly reimagining books. I swear I saw the shining fish – and laughed and asked – ‘is it a tench?’

Seeing them would be confirmation, douglass. Her question was how to falsify. Falsifiability is a principle that separates metaphysics from science. Claims that are not falsifiable in principle are metaphysics. Unicorns are not metaphysical beings. So, it is falsifiable in principle. Find unicorns and show that they dont cause wind.. If you cant find a unicorn that doesnt mean they are unfindable in principle. If you find one and show that it doesnt cause wind, then you have falsified the theory. So, it is possible in principle to falsify the theory. That seperates it from metaphysics.
For background on the principle of falsifiability start with the logical positivists. That will contextualize it for you, as opposed to the version you might hear at the local pub or from beth

Willard.
Yes, don’t ask such embarassing questions about Popper. why study science scientifically? I did read that piece in the australian ( I think) I found that somebody was selling a finding that was “not wrong” for a lot more than it was worth. On a side note, when chatting with ravetz, we did come to a point of agreement.. the death of philosophy was announced prematurely. so, this whole debate is not a total loss.
BTW Im still meaning to get to waltons (?? was that his name ) dissertation.

No Douglas we are not asking anything. Question marks would be a clue there. We probably wouldnt ask you anything given your propensity for not answering direction questions. Instead I am pointing out a fallacy in your thinking by constructing an example to show the hole in your thinking. Sometimes instructors ask questions. Sometimes they make points. Pretending that we can only ask questions and then taking note that we dont ask one as an exit strategy is bad faith.

Why ask questions when easy assumptions and indirect accusations are more fun right? Its Ok, I don’t mind. Some are here for fun and why not?
I have answered all questions (as far as I can see). You in contrast have ignored most — and have a reputation for it (I’m new here but see e.g. http://judithcurry.com/2013/01/31/condensation-driven-winds-an-update-new-version/#comment-291069
Quote tallbloke | February 2, 2013 at 7:32 am | Rep:
“be advised that Steven Mosher is a drive-by shooter who never comes back to face criticism of his illogical assertions. He is a waste of your time”
Well I have disproved the last bit: “never comes back to face criticism of his illogical assertions” — should have been “almost never”– evidence and falsification have their values.
Anyway, have fun and take care.

simple beth. Show that unicorns do not cause wind. Sheesh. We have a theory. Unicorns cause wind. After copious review everyone agrees that theory was not wrong. Now we are looking for evidence. For my part I am following on on the fairy line of evidence. Fairies are friends of unicorns. Faires live in the forest. Therefore, unicorns will be found in forests close to fairies. You’ve never seen one in the open have you? And of course it ties in with the rain as well. Because when it rains you see rainbows. rainbows, fairies and unicorns. It all fits. And my parents wondered what I would do with philosophy. Find unicorns!

Well at least we agree the ideas should be tested to be science. Though you sound a little imprecise on the details. You can chase your unicorns and we can seek constructive engagement with researchers who are open to our ideas (there are inceasingly many). Feel free to keep us posted how you go.

What Mosher and others tend too overlook,is that the fluid equations do not have a fundamental nature ,they are phenomenological equations a l imitating constraint on the prevailing theory of which very little can also be said such as Emanuel’s excursion in Flatland.

This could be an interesting debate – about whether the paper “should” have been published.

At the two extreme ends of the spectrum, we have to equally unsatisfying positions (IMO): (1) that a study that goes against convention has a higher standard and, (2) that a study is valuable because no one has proven it wrong.

Now I think that willard has made a strong case criticizing the way that this paper’s authors take Held’s comment out of context – but even still, the question of whether or not a counter-convention study should face a higher bar is an interesting one, IMO.

The problem with this discussion, as with so many discussions in the climate debate jr. high school cafeteria food fight, is that many involved have twisted the arguments away from a matter of philosophy to a matter of furthering partisan agendas.

In the end, because there is more interest in Jell-o flinging than the philosophical debate, I am left with this: There is no answer as to whether the study “should” have been published. The editors decided to publish it. Everyone will survive. And if they hadn’t so decided, despite hand-wringing and claims or inferences of victimization, the authors would have survived, and been free to do what so many authors of papers do when their studies are rejected for publication: look to publish in another journal – perhaps one with a lower impact factor – or make substantial revisions and try to publish elsewhere, or move on to something else.

What I find amusing here is that some people want to hold hostage, the philosophical debate about tenets of good science, to score points in the climate debate war.

Joshua,
Yes, if you have followed the main author as long as I have you would know that she will never engage willard on his direct question. And then she will say she has answered him or will chnge the topic. Now, the really striking thing is that I know you know nothing about fluids. yet, in watching her avoid willard you do get a sense of how the reviwers of her math felt. BTW, I’m beginning to like your notion of accountability. Although, I think most folks think admitting they are wrong is enough.
( referncing the lynas comments you made at keiths )

Joshua “some people want to hold hostage, the philosophical debate about tenets of good science, to score points in the climate debate war”

It appears you may be right. Do you believe that outsiders publishing in an open review, open access climate journal, and now asking for scrutiny are doing something crazy? Is it possible to win them over with an idea that challanges the status quo?

Do you believe that outsiders publishing in an open review, open access climate journal, and now asking for scrutiny are doing something crazy? Is it possible to win them over with an idea that challanges the status quo?

I think that Michael’s point stands. The notion of “outsider” assumes a sense of victimhood. I get bored with all this victimhood (and focus on rhetoric). It seems to me that some combatants on both sides are more interested in vindicating their sense of victimhood than almost anything else.

That said – let’s move beyond your “rhetorical device.”

No – I don’t think that it is even remotely crazy for anyone to publish in an open review, open access climate journal – and then ask for scrutiny.

in fact, I think it is a fascinating – and at least for me very much undecided – question as to whether such action furthers “science.” I can see merits in the arguments from both sides – and I suspect that those firmly convinced one way or the other are mostly suffering from binary mentality disease.

I have some reason to question motivated reasoning here – as I read somewhere in the websites associated with your group some rhetorical reference to climates scientists wanting to impose restrictions on the global economy (paraphrasing, and open to correction) – which I wonder if you’re willing to address. Please note, questioning the existence of motivated reasoning is not the same as questioning motivation And certainly it is logical to question the potential for motivated reasoning from those who are support “conventional wisdom” – (which in contrast to the potential of your own biases – you seem willing to offer as the operational rationale for the reaction among those who disagree with your findings). And certainly we have issues related to “novelty bias” and confirmation bias etc., etc. as you and willard discussed elsewhere – unfortunately, IMO, much to briefly.

But neither the potential nor the inevitable reality of motivated reasoning renders the philosophic debate irrelevant. The philosophical debate remains, IMO, irrespective of those factors (which are inevitable) and actually irrespective of the mathematical or theoretical validness of the technical aspects of the paper.

The basic problem, as I see it, is that people (in general) are too busy finger-pointing to take note of the ubiquity of biasing influences, and too busy claiming victimhood (and bad faith) to do what is necessary to control for their own biases.

Like I said. Same ol’ same ol.

But what is a bit unfortunate here is that the notion of open review and open access offer potential as vehicles to help to control for the impat of motivated reasoning. Perhaps this Jello-flinging is basically just growing pains – but I suspect not. If I were to consult my Magic 8-Ball, I am guessing it would tell me “Outlook not good.”

Joshua
Thanks – I am genuinely interested in all this. I have worked a fair bit in different cultures and do see myself as an advocate here with only a little time to pasue and look around. I dont see us as victims (well there are moments when I do) but the outsider issue is fairly fundamental to my reading. But as you say we all have our biases and delusions.
Thanks again. I’m going to mull this over.

Let me know if you want to talk after mulling it over. I see you making operational assumptions about your interlocutors (e.g., that which goes along with the identification of being an “outsider” as a description of your relationship to them), and acknowledging the ubiquity (in the abstract) of biases and delusions as an indirect way of not avoiding your own influences — but the rubber meets the road when you dig into the nitty gritty. Your thoughts seem more developed and specific in reference to others. I’d suggest that such a balance is the inverse of what is required to make progress.

FYI – I would be interested in knowing more about your reference to different cultures.

You might find it interesting that over at CaS, if you click past the jump in the Lynas post, you will see that Keith updated and crossed out another passage of the Lynas interview.

From Lynas:

I certainly apologise to the Soil Association for making a statement without sufficient evidence in the heat of the moment.

At least he apologized this time, and I’d say that this explanation ranks significantly higher on the accountability scale than his explanation for his previous error. In addition to the apology, this time he explains why he made the error. Still, I don’t think that he was sufficiently accountable – the “heat of the moment” component looks like a lame excuse to me. There was no real “heat of the moment” as his very own explanation makes plain. And even if there were a “heat of the moment,” he should simply leave that out of his explanation. Does it somehow “explain” his behavior to say that he allowed his emotions to trump his professionalism?

Still no editorial comment from Keith, however, despite that the topic of the post was Lynas’ credibility.

Thanks – The “nitty gritty” is perhaps where we need to go then … though I am not yet sure what that is. I am grappling with this (leaving all the hard work here to Anastassia and Victor today). Interested in thoughts. My responses to yours:

This process is interesting in itself as a (?) way to nudge science along in a transparent manner. Lessons? Would we advise others to do this? Why?

“Outsiders” – I think the first person to use this label was Judy (she used it again in the review). While it carries some baggage (as any such term does) she used it for a valid reason. We clearly were not “insiders” and we didn’t know all the conventions. All groupings, however arbitrary, seem to develop a sense of ‘us vs. them’ — this has numerous implications for communication. We are not members of the audience we’re trying to reach here (the main climate science community).

My point about different cultures is not a deep one. Its about recgnising the variaton in norms and rules and how they govern interactions. When I first went to Bangladesh (very young) I grew a beard as I knew that no one would take a beardless man seriously. If I work in remote communities (e.g. in Papua) I am always careful to get properly introduced to the leaders, be respectful, repeat consistently why I am there, win trust (listen, share humour, food etc). Its easy to make mistakes: this can be hilarious or dangerous. Anyway … a blog community has its own culture. Plenty of scope for fun and disaster and for anthropologists.

“indirect way of not avoiding your own influences” — well self delusion is likely. (By chance I do know a little of the large background literature on bias and self-delusion… should make me more alert … at least I acknowledge that self delusion occurs in everyone). Can’t I just be here because I want to know if this theory is correct or not, and this is where it has led? (my claim). Where should we go to find these subconcious “influences”? Not simple.

Just thoughts.

I’ll come back to your motivation issue in a moment (you are direct without making accusations — that’s welcome).

“I have some reason to question motivated reasoning here – as I read somewhere in the websites associated with your group some rhetorical reference to climates scientists wanting to impose restrictions on the global economy (paraphrasing, and open to correction) – which I wonder if you’re willing to address.”

Great – thanks. Good question.

Well we are not an ideological group. We simply don’t talk about that.

I can speak for myself: Certainly I am pro-forest and pro-people (I have worked with tropical conservation a long time) but I am also critical of a dogmatic approach to anything. I have often argued in favour of greater engagement with industry etc. or against imposing parks etc. when that seems counter-productive according to circumstances or data.

It would seem an implausible conspiracy: take years to come up with a convincing theory with supporting evidence and then spend a lot of time and effort getting it into a difficult journal and stopping by every now and then to invite the critics to help identify the flaws. Then say it is a distinct issue to greenhouse gas arguments. I admit a few assumptions there … but it’s not a story line I would write for a conspiracy novel. Let me know if you see a plausible narrative that fits.

Say we find gaps or errors in the current theories of how we understand how the climate works. What should we do about that? We can try and share them right? What other options are there? Good science needs critical thinking and debate all the time (for and against the status quo). It doesn’t need dogma.

This process is interesting in itself as a (?) way to nudge science along in a transparent manner. Lessons? Would we advise others to do this? Why?

I don’t think the choice is binary. It’s like saying that allowing access to code is a good thing. I think that as a general concept, it is a good thing, but I think that there may be legitimate questions about whether or not, for example, it would hamper free-ranging scientific inquiry. So sure – I think that the “process” you’re engaged in is a good thing, but to the extent it becomes part of an agenda the benefits are reduced, IMO. This is why I continue to dislike the notion of “outsider” – as it seems to me to only perpetuate the problems, and suggest an agenda.

“Outsiders” – I think the first person to use this label was Judy (she used it again in the review). While it carries some baggage (as any such term does) she used it for a valid reason. We clearly were not “insiders” and we didn’t know all the conventions. All groupings, however arbitrary, seem to develop a sense of ‘us vs. them’ — this has numerous implications for communication. We are not members of the audience we’re trying to reach here (the main climate science community).

Yes – all groupings create some form of institutional behaviors, norms, and in the end, biases. But what group identification is operational for your “insiders?” Is it that they are serious analysts? Is that they are people knowledgeable in the relevant field? Or is it that they are tribe members protecting their territory? Chances are, IMO, all those identifications are operational to different extents with the different people involved. By choosing to identify them as some unspecified tribe of “insiders,” by picking one those groupings to the exclusion of the others, you are assuring a perpetuation of the tribal status quo. Shouldn’t you be making that their primary identification is that of serious analysts? If so, then why would they be “insiders” and you “outsiders,” since you share that important attribute. This is why I am speculating about seeking vindication for victimization – your choice of how you are identifying your interlocutors.

My point about different cultures is not a deep one. Its about recgnising the variaton in norms and rules and how they govern interactions. When I first went to Bangladesh (very young) I grew a beard as I knew that no one would take a beardless man seriously. If I work in remote communities (e.g. in Papua) I am always careful to get properly introduced to the leaders, be respectful, repeat consistently why I am there, win trust (listen, share humour, food etc). Its easy to make mistakes: this can be hilarious or dangerous. Anyway … a blog community has its own culture. Plenty of scope for fun and disaster and for anthropologists.

I work mostly with international clients and students. The focus of that work is often in exploring cultural differences (and in particular, cultural differences as they relate to differences in communication styles and rhetoric) – but I frequently find that I need to check myself against the habit of mistakenly attributing differences to culture. Often, I miss intra-cultural differences in my zeal to theorize inter-cultural differences.

I also work with American students in exploring how cultural differences in the US play out in academic settings. Indeed, I am often trying to help students maintain a sense of healthy identification with their own cultural identity even as I am trying to encourage them assimilate so as to be able to maximize their success in a “culture” that stresses different attributes than might have been stressed in their prior life experiences. Balance is key. The losers in blog discourse, IMO, are those so wedded to their ideological predispositions (“culture”) that all they do is repeat themselves; they never learn nor help others to learn.

Can’t I just be here because I want to know if this theory is correct or not, and this is where it has led? (my claim).

When you say “want,” you speak of motivation. Your motivation may very well be to want to know if your theory is correct or not. I assume that to be your motivation. But “motivated reasoning” is different than motives – and motivated reasoning must be accepted as a given if it is to be controlled. Do you really think that it is likely that you are without the reasoning biases that incline you to filter data and evidence so as to confirm your preconceptions?

Where should we go to find these subconscious “influences”?

That is what dialog is for. It could be what blogs are for – although it doesn’t take long to see that it’s like looking for a needle in a haystack.

Well we are not an ideological group. We simply don’t talk about that.

I believe you don’t talk about that – but how do I reconcile that against what I read about climate scientists seeking to impose policies? Sounds ideological to me.

I can speak for myself: Certainly I am pro-forest and pro-people (I have worked with tropical conservation a long time) but I am also critical of a dogmatic approach to anything.

Are you dogmatic about being anti-dogmatic? I see dogmatism on both sides of the fence in all these issues. I also see flexibility on both sides. I am skeptical of anyone who leans towards identifying dogmatism with ideology – as opposed to seeing that based on what we know about the intrinsic qualities in how we reason, we all need to control for a tendency towards dogmatism.

It would seem an implausible conspiracy: take years to come up with a convincing theory with supporting evidence and then spend a lot of time and effort getting it into a difficult journal and stopping by every now and then to invite the critics to help identify the flaws. Then say it is a distinct issue to greenhouse gas arguments. I admit a few assumptions there … but it’s not a story line I would write for a conspiracy novel. Let me know if you see a plausible narrative that fits.

I don’t believe in conspiracy theories. I don’t suspect a conspiracy here. Knowing that motivated reasoning is a reality does not assume a conspiracy. The plausible narrative is that you and your colleagues are serious about your work – and that like anyone, you are inclined towards confirmation bias, towards tribalism, towards as sense of victimization.

Say we find gaps or errors in the current theories of how we understand how the climate works. What should we do about that? We can try and share them right? What other options are there? Good science needs critical thinking and debate all the time (for and against the status quo).

Agree.

It doesn’t need dogma.

IMO – you’re better off leaving that last sentence off. It suggests that you are saying that someone here is arguing in favor of dogma. It becomes a self-fulfilling prophecy, IMO

Joshua
many many thanks for that. I appreciate the feedback and concede the wisdom in your points. (I am definitely dogmatically anti-dogmatic on occassion — that one is going to haunt me.)
Thanks again

(1) The paper is highly controversial, proposing a fundamentally new view that seems to be in contradiction to common textbook knowledge. (2) The majority of reviewers and experts in the field seem to disagree, whereas some colleagues provide support, and the handling editor (and the executive committee) are not convinced that the new view presented in the controversial paper is wrong. (3) The handling editor (and the executive committee) concluded to allow final publication of the manuscript in ACP, in order to facilitate further development of the presented arguments, which may lead to disproof or validation by the scientific community.’

This is from the editors comment at the end of the paper – and cites some support – we can include Tomas in that – and a bunch of people who are withholding judgement. I am in the second group solely because my mind works far too slowly too reach judgement too soon. I build a visualisation of the processes – dip my toes randomly into the math – and eventually form a whole and see if my picture matches the math. It takes a long time. But the objections to the processes I have seen seem wrong, banal, uninformed or blatantly ludicrous.

The comments descend to the trivialities of unicorns and pirates as an epistemological analogy from a plethora of epistemological wankers. Pirates and unicorns – whatever symbology is involved – have about as much place in science as God – one way or the other.

One myth that needs revealing is that this is in the spirit of objective enquiry – that there is an equivalence in confirmation bias between two diametrically opposed tribes. Whatever stories you tell yourselves superficially in the objective idiom of science. Perhaps there is – and it is far from obvious that one side or the other has any absolute claim to scientific truth. Indeed – any claim to absolute scientific truth seems a priori a social construct rather then a scientific one. On one side there is a groupthink dynamic – moral certainty, collective rationalisation, an illusion of unanimity, steorytyped views of outsiders, gatekeepers. The other side seems defined by opposition as conservatives always are.

Neither side is likely to be scientifically correct – at this stage in the evolution of climate science there is only speculation and the ‘jiggle-jiggle-jiggle or the wiggle of the path.’

Joshua what would suffice as accountability.
‘I said something without checking it in the heat of the moment?
Do you want a report on his internal state when he said it?
How do you check that?
His admission to me and his account of why he made it ( heat of the moment) seem about as deep as one can credibly go.
“I did it in the heat of the moment and you know I felt under pressure and under attack and I have a bit of an ego problem that comes from having a bad childhood..” I mean how deep do you want him to go. I suspect you will doubt whatever he says until his report of why he did it agrees with your speculation of why he did it. Maybe he was having a bad day. I can tell you I have said wrong things soley because I was in a rush, got a phone call, and hit the submit button. I suppose a real explanation would not suit you. Finally, you are asking for something that you cannot check.
So, why do you ask for accountability?

His admission to me and his account of why he made it ( heat of the moment) seem about as deep as one can credibly go.

An admission of responding “in the heat of the moment” seems like a weak rationalization to me. It seems offered as an excuse rather than simply an explanation.

These are relative issues. Certainly, if you hauled off and shot someone who did nothing deserving, because they ticked you off – saying “Well, I responded in the heat of the moment” is not considered being accountable.

Obviously, Lynas’ error is nothing like shooting someone, so the comparison is not a direct one, but I think that while Lynas showed more accountability than he did with the prior error, there is still room for improvement.

He could simply have said something on the order of: I made an accusation without having taken the time to properly investigate the facts. There is no excuse. It was unprofessional. I apologize. I re-double my pledge to not make the same sort of mistake in the future, as I realize that any time I do that, it lowers my credibility. Since my credibility was the very subject of this post, I understand and acknowledge the importance of my errors.

“I did it in the heat of the moment and you know I felt under pressure and under attack and I have a bit of an ego problem that comes from having a bad childhood..”

This reminds me of how neocons responded to the argument that it is relevant to look at how our actions w/r/t why we get attacked by terrorists: “Those libz think we should offer Osama bin Laden a blankie and a therapist.”

. Maybe he was having a bad day.

So saying he was having a bad day shows accountability for a professional journalist to make an accusation that he hadn’t done due diligence in investigating – in an interview where his credibility was the subject? Nope. I can’t go with that.

Finally, you are asking for something that you cannot check.

Sure, he could say something on the order of what I suggested above, and be lying. It is possible. But it is implausible. What could possibly be the motivation for him to lie in such a way? What would be be covering up by lying in that fashion?

The more I look at the details of the paper the more totally it seems to be wrong.

Now I have looked at the chapter 3.3 pressure profiles in moist versus dry air columns.

In that chapter two columns are defined, moist and dry. The problems are in the handling of the moist column that seems to be physically total nonsense.

They start defining a static isothermal column with saturated moisture at the bottom. The static nature is taken literally and results in independent barymetric profiles for dry air and vapor as indicated by the sentences:

Water vapor in column A is saturated at the surface (i.e., at z = 0) but non-saturated above it (at z > 0). The saturated partial pressure of water vapor at the surface pv(Ts) (Eq. 4) is determined by surface temperature and, as it is in hydrostatic equilibrium, equals the weight of water vapor in the static column.

While that’s theoretically correct and consistent it’s difficult to see any relevance choosing such a column as starting point as nothing like that can ever occur in real Earth atmosphere at latitudes less than 100 km.

Then they add the moist lapse rate to the column and calculate the vapor profile in the modified column. They conclude properly that the column with moist lapse rate cannot sustain as much water vapor as the isothermal static column. As there’s less vapor in the column with lapse rate the pressure is reduced at the bottom.

The above makes sense for a column in a vertical pipe with walls that keep the amount of dry air fixed in the column. In a atmospheric context more dry air will automatically enter the column when water is removed. The formula (27) that calculates the change in the pressure in column A does not have anything to do with the real atmosphere. Nothing derived from that has any relevance on anything that happens in the atmosphere as far as can see.

It may be that little in the remaining paper beyond equations (28) and (29) depends on the equation (27), but why to include such nonsense in the paper at all?

Pekka Pirilä
Great that you want to work through this.
Here’s some homework for you if you really want to get to grips with the two different views.
I think you’ll like this: Meesters, et al. Comment on “Biotic pump of atmospheric moisture as driver of the hydrological cycle on land” by A. M. Makarieva and V. G. Gorshkov, Hydrol. Earth Syst. Sci., 11, 1013–1033, 2007, Hydrol. Earth Syst. Sci., 13, 1299–1305, doi:10.5194/hess-13-1299-2009, 2009.
But then see also the replies here Makarieva, A. M. and Gorshkov, V. G.: Reply to A. G. C. A. Meesters et al.’s comment on “Biotic pump of atmospheric moisture as driver of the hydrological cycle on land”, Hydrol. Earth Syst. Sci., 13, 1307–1311, doi:10.5194/hess-13-1307-2009, 2009.
Hope that helps

Trying to go further in this paper seems also impossible. In my view discussion of horizontal pressure gradients in the spirit of chapter 4 can be done properly only by starting from the description of a circulating system that’s realistic enough for allowing a comprehensive analysis as an isolated system. It’s essential that the subsystem being considered does not interact with other parts of the atmosphere in a way that may affect essentially the conclusions, but which remains unknown quantitatively.

Already in an early comment in this thread I speculated that it may be impossible to do those analyses without the use of a full model of circulation. (Not necessarily a GCM of the whole atmosphere, but a CM anyway.)

Horizontal gradients cannot be discussed reliably looking only at two columns and postulating how they interact at various altitudes, a much more comprehensive approach is needed. When a system is understood in detail, it’s often possible to present simplifications known to be true based on the more detailed analysis, we can read descriptions of such in any good textbook. Trying to guess the simplified equations without the help of a more comprehensive picture is, however, likely to fail. At minimum it’s impossible to convince others of the validity of the approach.

The problems that I have with those parts of the paper that I believe to be able to judge directly make me more than doubtful on the relevance of those parts that lack the required full context.

The paper discusses pressure changes from removal of vapor as if there would be a change from a state with much more vapor to one with less. The situation is, however, discussed as stationary. Thus the amount of vapor in air does not change at all. it remains constant at every altitude. When air ascends water condensates but new water enters at the surface.

There’s no overall pressure difference from the condensation, there are different vertical profiles for the dry and the moist column. That leads to horizontal pressure differentials. That’s true, whether the change in air stoichiometry is taken into account or not in the calculation of the moist column. Taking the stoichiometry into account has a small influence that’s often left out. Otherwise the standard analysis is fine.

Pekka, yes, see my remark above (search for “refrigeration”). They make a thermodynamic error in setting up the two columns where they neglect the pressure reduction that should go with their cooling. Everything that follows that set-up is a comparison of two independent columns because of this error. There is no reason a pressure gradient between thermodynamically independent columns can tell you anything useful.

@PP (in response to Sect. 3.3, 1st par.): While that’s theoretically correct and consistent it’s difficult to see any relevance choosing such a column as starting point as nothing like that can ever occur in real Earth atmosphere at latitudes less than 100 km.

My reaction exactly. Why not just start with the environmental lapse rate ELR of two columns set to the appropriate MALR and the DALR respectively? (Possible answer: so as to define a specific level of moisture at each altitude that will become supersaturated when the ELR is raised as in the 2nd par. But if so, isn’t that a weird way of getting this effect: why not start with the MALR and just add extra moisture? At the very least some explanation of this seemingly strange choice would surely be in order.)

Sect. 3.3, 2nd par: Now the columns cannot be static: the adiabatic lapse rates are maintained by the adiabatically ascending air.

I don’t see this: what’s preventing them from being static? In the 1st par. ELR = 0 which is way less than the MALR hence the column is absolutely stable. But that’s true for any ELR less or equal to the MALR, whence raising the ELR to the MALR (which in the case of the dry column equals the DALR) as done in the 2nd par. cannot disturb stability (though it can cause condensation in the first column if it makes the air supersaturated). What would cause air to ascend in this setup? Not diffusion since all that does is to very slowly reduce the ELR, increasing stability. I don’t understand this at all.

Sect. 3.3, 3rd par: The change in pressure \del p_s in column A due to water vapor condensation is equal to the difference between the initial weight of water vapor pv(Ts) and the weight of saturated water vapor:

How could that difference be other than zero? Pressure at any altitude is exactly the weight of the molecules above unit area, independent of their phase (whether vapor or liquid), so phase changes can’t cause pressure changes. Furthermore the volume V = NkT/P should stay more or less constant since k and P are constant while NT (product of number N of molecules with temperature T) should also remain roughly constant because although N has decreased very slightly, this is offset by the corresponding slight increase in T. (This is how I would address Eli’s concern that condensation violates the ideal gas law.) Even if NT isn’t exactly constant I don’t see how it could change enough to cause any significant draft, either vertical or horizontal. (Some of this echos Pekka’s concerns.)

Sect. 4.1, 1st par. We have shown that condensation of water vapor produces a drop of air pressure in the lower atmosphere up to an altitude of a few kilometers, Fig. 1c, in a moist saturated hydrostatically adjusted column.

I would like to see Section 3 argued more rigorously before I could accept this “We have shown” claim. It seems to me that it’s much easier to show the opposite conclusion, namely that condensation doesn’t cause any change in pressure, and at most an insignificant change in volume if any.

@PP: As long as I find essential weaknesses (and outright faults that are not explained/admitted) in its argumentation I’m less tempted in looking at the biotic pump.

There are too many errors, as well as too many easily disproved claims, up to Section 3 for there to be any point in pursuing this further.

I agree on that, but presenting the issue with an accuracy where that matters we should consider also acceleration at different altitudes in the motion of the ascending air. It’s accelerated at every altitude as its pressure goes down and its density follows at a lesser rate. The condensation of water does also reduce a little this acceleration.

All these details are at a level that can be safely left out for most purposes.

capt.d., a pressure change can cause condensation and that happens naturally all the time. It may happen that condensation causes a pressure change but that requires some cooling by other means, e.g. condensation on cold glass, which we don’t see so much in the free atmosphere, so I am skeptical of this process.

capt.d., I will correct what I said slightly. Fog formation is a process where condensation occurs by radiative cooling, so there are processes that may do this, but these are radiation-produced clouds, not the subject of the paper in any way.

JimD, “capt.d., a pressure change can cause condensation and that happens naturally all the time. It may happen that condensation causes a pressure change but that requires some cooling by other means, e.g. condensation on cold glass, which we don’t see so much in the free atmosphere, so I am skeptical of this process.”

You really shouldn’t be skeptical of the process, just skeptical of the magnitude of the impact of the process. On a summer afternoon a “shower” can dump three inches of rain per hour. Once condensation starts in a super saturated cloud you have all the dynamics involved, but it takes water vapor to get the ball rolling. That is the biota effect, green space, local wet land restoration, reduction in non-permeable surface the whole smire.

Their size can be easily estimated with some accuracy, and I’m sure that has been done very many times by people studying atmospheric physics. I have some feeling of the answers but not at a level that I would be ready to make public even here.

The influence of condensation on the volume and density of moist air is also understood by every scientist working on these issues. Most may have given little thought on them but it’s not credible that there were not also many who have had a bit closer look on them.

Pekka, “The influence of condensation on the volume and density of moist air is also understood by every scientist working on these issues. Most may have given little thought on them but it’s not credible that there were not also many who have had a bit closer look on them.”

That would depend on who you ask. Weather models get into more detail and have adjustments to virtual temperature etc. to make things work. Climate models assume constant condensation and neutral sensible heat exchange. You might note that sensible and latent were the two biggies that Stephens “corrected” in his energy budget plus the “window” flux which interacts with cloud moisture.

Concerning climate science we must take into account the level of detail they have. What can one do with the size of grid cells used in GCM’s? Certainly not much of what has been discussed in this thread in a explicit way. Whether the parametrizations include them implicitly cannot really be told.

@NiV: Only if there’s no net vertical acceleration. If the condensed liquid is in freefall, it doesn’t contribute to the surface pressure.

Indeed. That’s a lot clearer than what’s in the paper.

Not that precipitation spends much time accelerating, let alone at g (free fall). The more relevant situation is precipitation falling at terminal velocity, since that causes a downdraft countered by an updraft surrounding it. Such vertical winds can be extremely strong.

@PP: All these details are at a level that can be safely left out for most purposes.

@NiV: That’s the question.

Easily answered. The pressure lost due to accelerating rain is recovered when the rain is decelerated by hitting the ground. If m kg/sec of anything traveling at velocity v collides with an area A with no rebound the resulting pressure is mv/A. (Double that for perfectly elastic rebound.) For rainfall of one inch/hour (fairly strong), m/A = 2.54*10/3600 = 0.007 kg/sec/m2. Rain falls at a terminal velocity of 5 m/s more or less depending on drop size whence the pressure is m/A * v = 0.007*5 = 0.035 Pa or 350 parts per billion (ppb) of atmospheric pressure.

But the rain itself is the wrong thing to look at. At a pressure where air has a density of 1 kg/m3 (a few hundred feet above sea level, at sea level it’s around 1.2 kg/m3), air of velocity v striking a flat surface develops a pressure of v^2 Pa. This is because m/A in the above no-rebound formula mv/A is itself v kg/sec/m2. This is way more than the above m/A of 0.007 kg/sec/m2 for rainfall of one inch per hour, so a downdraft has orders of magnitude more influence on pressure than the acceleration and deceleration of falling rain.

But the terminal velocity of rain is measured only with respect to the air. If in falling the rain drags the air down with it, the rain might be falling 5 m/s faster than the air but the air itself can be driven downwards at speeds up to 30 m/s, see e.g. page 2 of http://kiwi.atmos.colostate.edu/rr/groupPIX/daniel/thesis.pdf . A downdraft of that speed colliding with a flat surface (e.g. the wing of a plane) will therefore develop a pressure of 30^2 = 900 Pa or about 1% of atmospheric pressure. This makes the above 350 ppb for rain hitting the ground after the downdraft has dissipated higher up look pretty puny!

For those who prefer experiment to theory there’s a straightforward way to actually measure the pressure of rain striking the ground. Put out a scale in the rain with a fine mesh held over it to break the fall of the rain without however preventing the rain from landing on the scale (by allowing it to leak through the mesh). When equilibrium is reached zero the scale. Now remove the mesh and note the weight in grams resulting from the rain striking the scale directly. Divide by 100 to convert to newtons. This is the force needed to break the fall of the rain. Divide by the area of the scale surface to give pressure.

For a platform of area 0.1 m2 (about a square foot) expect less than a gram of force, so either use a very sensitive scale or increase the catchment area to more like a square meter. Rain develops very little pressure on the ground and is therefore very tricky to measure.

@captdallas: If you have a pressure differential of 1″ w.c. it can produce a velocity pressure of 4005 fpm. 150 fpm only needs a vp of 0.01 ” w,c. Small pressures over large areas equal stuff moving.

cd, I agree exactly with your first sentence when the coefficient of drag (if that makes sense in an HVAC context) is exactly 1. In metric that would be 250 Pa at a velocity pressure of 20 m/s (assuming air at STP with density 1.25 kg/m3). (250 is exactly 1.25 * 1/2 v^2 where v = 20; the formula v^2 I was using is for a flat plate, which has a coefficient of drag of 2.)

However when you reduce the velocity pressure by a factor of 4005/150 = 27, shouldn’t the corresponding pressure be reduced by a factor of 27^2 or around 700, which would call for a vp of 1/700″ = 0.0014″ rather than 0.01″? If your 0.01″ figure is correct then I’m surprised that conventional physics gives exactly your result in the first case (assuming Cd = 1) but nowhere near it in the second.

I can also see where falling rain (which of course results from condensation) can easily cause air to move at the former speed, 20 m/s being reasonable for a strong downdraft.

What I’m completely failing to see is any connection between the associated pressure differentials that such velocities can induce when colliding with e.g. stationary air or the wing of a plane, and the mechanism of condensation itself.

Regarding the collapsing can video, how is this adiabatic? If you had no water at all but simply heated the air in the can (in the manner of a hot air balloon but with the air very much hotter) and then plunged the inverted can into the cold water, wouldn’t the decreasing pressure in the can as the water cools the air inside cause the can to collapse anyway?

As I understand the article it is claiming that adiabatic condensation decreases pressure in the atmosphere, which is the bit I’m having trouble with. The experiment in the video is nowhere near adiabatic. I’m fine with atmospheric pressure changes resulting from non-adiabatic processes, or from wind etc., but not from condensation alone.

capt.d., to go back to your first question. Condensation in ascending air does cause a pressure change which is net positive. This is only briefly before the air expands due to latent heating to equalize the pressure (Pielke commented on these fast adjustment processes due to sound waves). The heating has several times more effect on the pressure and final density than the loss of vapor. This is another flaw in the thinking that condensation leads to a pressure reduction, because the latent heating effect is completely missed. With zero latent heating, yes, the pressure would reduce, the density would go up as air fills in the deficit, and clouds would sink. Not very realistic.

JimD, it is like most non-linear dynamic systems, there is a “sweet spot” or bifurcation point where different variables have maximum impact. If you consider a hurricane, it can grow too large and the squall bands choke the inflow of moist air. When a storm system moves across land, the rate of moist air inflow decreases with the available moisture. The paper misses the critical dimension by assuming there is no limit to X, when the limit of X is the point.

They get into ratios of height to width later when they should mention that the limit of X on the impact is critical. Where is the “sweet spot”?

The idea seems intuitively correct for circulations such as Hadley Cells or for the rain pumps known as rain forest. That evaporation and condensation is a dynamic process – which is pretty much as described in the paper – goes without saying and makes no difference at all.

Robert,
Makes all the difference and solves a meteorological paradox. Take the Amazon, to cite your rainforest and an example that served as insight to the development of the Biotic Pump Theory. If you look the last ten years of surface temperature both on the hotter Atlantic (http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MYD28M), where the trades gather steam (literally), and on cooler land (http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD11C1_M_LSTDA), where forest canopy is transpiring at great rates, you wonder how is that possible that winds blow from a region with warmer surface into another region with colder surface – for thousands of km inland, year round? You could think of winds accelerated by Earth spinning etc. But the tropical Atlantic trades gather on the northern hemisphere, blow South, cross unceremoniously the Equator, enter South America and travel down to latitude 30 S in the austral summer.

Our theory solves the paradox as it clearly puts and physically explains the low pressure over the Amazon (higher evaporation and condensation due to the forest) that “pulls” the tropical Atlantic trades over land, down deep into the southern hemisphere. In such a scenario, surface temperature per se is not an issue. If it works intuitively for you, and if it works physically for the Amazon as our theory demonstrates, how could it not work elsewhere?

Vaughan,
See climatological wind fields over the ocean around South America, (Climatology of Global Ocean Winds). The seasonal fluctuation of the Inter Tropical Convergence Zone (determined by Earth axis tilt) plays a role in determining how much air comes in, at different seasons, from the northern hemisphere into the Amazon. But the proof that air from northern hemisphere does cross the Equator is the long-known landfall of Saharan dust on the Amazon (e.g. African dust keeps Amazon blooming). The sucking-in of trade winds at the mouth [roughly between longitude 45o and 54o] of the Amazon’s south-western-bound “aerial-river” is evident, year round. Tropical Atlantic SST is always warmer than the amazonian LST.

@AN: See climatological wind fields over the ocean around South America, (Climatology of Global Ocean Winds).

Ah, thank you. Looking along the equator I see the arrows pointing inwards (hence south) towards the Amazon, just off-shore. According to the paper’s theory this direction is the result of condensation-induced pressure reduction over the tropical Amazonian rain-forest, right?

How do you show that the direction is not simply that of off-shore sea breezes? If you look along the equator to the east the arrows orient themselves upwards to point to the coast of Africa, even more strongly. Why can’t these be accounted for by weak sea-breezes into the Amazon (which having more forest is cooler than Africa) and strong sea-breezes into Africa, which being drier is hotter than the Amazon?

Also the map only shows the tropics. Where is the evidence that wind blows from the Northern Hemisphere to 30 S in the Amazon?

But the proof that air from northern hemisphere does cross the Equator is the long-known landfall of Saharan dust on the Amazon (e.g. African dust keeps Amazon blooming).

But the whole Atlantic is blowing east to west year, and the portion from the Sahara seems to be blowing more into Central America than South America. I can see that a little bit of Saharan dust would be helping the Amazon but then one would expect even more to be dropped on Central America (which might not notice however since its need for nutrients is not as critical as the Amazon’s).

The sucking-in of trade winds at the mouth [roughly between longitude 45o and 54o] of the Amazon’s south-western-bound “aerial-river” is evident, year round.

Again, how do you distinguish “sucking in” from a generally westward wind blowing across the whole Atlantic (whether pushed or pulled), slightly shifted south in the manner of ordinary sea breezes, namely by rising warmer air over the land than the air over the Atlantic.

Vaughan,
Sorry not responding promptly to your valuable questions. I’ve just fathered a baby-girl few days ago, domestic life is quite busy, I’ve had not much time to follow this thread. I guess I missed adding here the climatological wind fields for South America, which should quench your justified thirst for data. While I search and find a suitable link to illustrate my statements, believe me, ocean trades that turn in towards the Amazon continue inland, in a SW direction, for more than three thousand km til they reach the Andes barrier and split, deflecting NW (minor branch) and SW (larger branch that keep going till Argentina during austral summer). If you look, these low altitude flows counter the usual direction of the Hadley circulation at those levels over adjacent oceans, specially during the austral summer, but not only. Sorry again for missing the links, which I hope I will be able to post soon.

Correction: “ocean trades that turn in towards the Amazon continue inland, in a SW direction, for more than three thousand km til they reach the Andes barrier and split, deflecting NW (minor branch) and SE (larger branch that keep going till Argentina during austral summer).”

=> South East is the outgoing flow direction from the Amazon into meridional South America.

Thank you Antonio. Intuition is little vague – it is more visual reasoning that I was referring to. A proto language and proto math of consciousness. Am I being mystical? After visualisation comes rigouress math or language precision.

“The words or the language, as they are written or spoken, do not seem to play any role in my mechanism of thought. The psychical entities which seem to serve as elements in thought are certain signs and more or less clear images which can be ‘voluntarily’ reproduced and combined. …. This combinatory play seems to be the essential feature in productive thought before there is any connection with logical construction in words or other kinds of signs which can be communicated to others”. Albert Einstein in a letter to Jacques Hadamard.

Now I suppose I will be accused of comparing myself to Einstein. Last week it was Walt Whitman. The Climate War has unanticipated battlefields. Good luck.

Feynman continues: “What I am really trying to do is bring birth to clarity, which is really a half-assedly thought-out-pictorial semi-vision thing. I would see the jiggle-jiggle-jiggle or the wiggle of the path. Even now when I talk about the influence functional, I see the coupling and I take this turn – like as if there was a big bag of stuff – and try to collect it in away and to push it. It’s all visual. It’s hard to explain.”

Schweber: “In some ways you see the answer – ?”

Feynman: “The character of the answer, absolutely. An inspired method of picturing, I guess. Ordinarily I try to get the pictures clearer, but in the end the mathematics can take over and be more efficient in communicating the idea of the picture. In certain particular problems, that I have done, it was necessary to continue the development of the picture as the method before the mathematics could be really done.”

I have experienced relativity as a flower opening in my mind over decades.

Visual thinking, also called visual/spatial learning, picture thinking, or right brained learning, is the phenomenon of thinking through visual processing.[1] Visual thinking uses the part of the brain that is emotional and creative, to organize information in an intuitive and simultaneous way.[citation needed]

Visual thinking is one of a number of forms of non-verbal thought, such as kinesthetic, musical and mathematical thinking.[citation needed]

Visual thinking may have a co-morbidity with dyslexia and autism.[citation needed]

Although the Feynman quote is more informative about the actual processes. But I note that ‘flow’ in music is one of the forms of non-verbal thought.

James McWilliams – eminent climate scientist that he is – is entirely in the realm of dense (in terms of meaning) and precise language. It took me perhaps a month to gain confidence that I understood even a fraction. Knowledge is the offspring of curiosity and diligent study. I suggest you try it some time.

Visual thinking is still cognition with semantical properties, not unlike playing chess, composing music, proving theorems in category theory or even kung fu fighting (think of the animal forms).

The brain acquired its perceptual system way before the verbal one, and it is quite clear that language has a perceptual source, as the Pinker presentation underlined. (Pinker also emphasized the interactional source, which satisfy ethological functions like dominance.) That makes me surmise that cognition is mostly situated, and that the traditional computational model of the mind is wrong. You can look for situated cognition to know what I mean by that.

***

What Einstein says rings true to me, and I should have said so. What I took objection to was the bit where he seems to say that what he experiences is beyond linguistic manifestations. According to he contemporary theories of mind I prefer, his experience could form a continuum with verbal languages.

In another life, I did some research on diagrammatic reasoning. I am a chess player, and a visual guy. I have lots of experience with autists.

My own experience is that most people tend to grasp faster concepts when expressed via multiple modalities. Think of encyclopedic dictionaries: you have images of concepts or objects, and the word expressing them below it. Logic would be easier to understand if logicians understood that formulae become non-sense quite fast:

Some people can do without the words. Some other can do without the images: Pierre Duhem, for instance, was against the use of models in science. We should not infer from that that the images stop to carry meanings.

I was merely describing how my thought processes work for these sorts of physical systems. Although I am not claiming any great correspondence – both Einstein and Feynman resonate as descriptions of the process.

But the distinction is between visual thinking and communication – vision and language. Different parts of the brain.

And Myrh – there is an imperceptible time dilation in everyday activities. It is measureable. That’s all that counts. Although Einstein did say that some things that can’t be counted – count as well.

It would depend on the details of the flow of air around the falling droplet, but there would be a definite answer. The drag-deceleration of the droplet will send out a pressure wave into the air, which when it contacted the surface would constitute the raised surface pressure – the circle of contact would define the pressure footprint.

NiV (is it fine if I call you this way?), thank you for your comments. I am very interested in this topic so if you have any other thoughts they’d be most appreciated. From what you said, consider that the falling droplet creates a surplus of pressure beneath itself. This local pressure anomaly sends waves in all directions, not only down to the surface but also in the horizontal directions. So where these waves actually contact the surface (what is the radius of that circle) is a big question. Any ideas?

Regarding Spengler et al. (2011) here is the link: Spengler, T., Egger, J., and Garner, S. T.: How does rain affect surface pressure in a one dimensional framework? J. Atm. Sci., 68, 347–360, 2011. They present graphs showing the time response of surface pressure following condensation. It can be seen that immediately upon condensation aloft (i.e. with a time delay set by the height and the speed of sound) the surface pressure drops and never returns to its value (while the droplets are falling down).
(Note that their latent heat idea is not correct, in our view, as we clarified in our comment. Basically what they studied is adiabatic condensation at constant volume which we show in our paper is not possible. They release latent heat as sensible. But they also have a set-up without heating.)

In all cases of interest the number of droplets is very large and they form and grow continuously. Therefore it seems clear that all the effects of pressure waves average out effectively and what’s left is the increase in pressure that results from drag forces on droplets at altitudes above the point of observation. The calculation can also be done averaging in horizontally.

Yes, the pressure wave is approximately spherical, expanding at the speed of sound. The radius of the circle will depend on how high the droplet was when it started falling and how long ago that was.

I had a quick look at the link, but unfortunately it’s paywalled, so I can’t read it. The phrasing of the abstract is ambiguous.

They say:
“It is shown that the rain formation leads to a change of the surface pressure after a short period of acoustic wave activity. There is, however, no hydrostatic surface effect once the particles reach terminal velocity. It is not until the rain reaches the ground that the surface pressure decreases consistently with the mass removed by the phase change.”

It’s not clear whether “no hydrostatic surface effect” means no further change (after the pressure reduces), or no reduced pressure (i.e. it is as it was before the drop started to fall).

In a 1D setting, I would expect the pressure to drop sharply at the instant of condensation, then rise slowly back to where it was as the droplet approaches terminal velocity, and then at terminal velocity it would remain unchanged at its initial value (i.e. no pressure drop) until it hit the ground. Then with the drag loading taken off, the air would relax and the pressure drop to the lower value corresponding to the weight of the air with the droplet removed.

This fits the abstract’s phrasing, but I can see how the first and second sentences quoted above could be interpreted as a permanent drop. But what about the third sentence? Doesn’t that imply the pressure doesn’t drop until the rain reaches the ground?

The 1D setting doesn’t tell the whole story, though. In 3D, the droplet falling at terminal velocity is continuing to radiate pressure changes, although these do not change the total pressure on the surface below. They change the distribution of forces in the air so as to continue to support the droplet at its moving location. The pattern of pressure changes on the ground will be more complicated, although it will still have to integrate up to the weight of the raindrop.

You can get an idea of the shape of this pressure field by considering two expanding spheres starting at the place/time the droplet condensed, and the droplet reached terminal velocity. They both expand at the speed of sound Outside the outer sphere, you get the initial background state. Inside the inner sphere you get the usual axisymmetric Stokes flow, of fluid flowing round a sphere, shifting downward at terminal velocity. Pressure change proportional to Cos(theta)/r^2 where theta is the angle from the downward vertical.) And in between you get a transition between the two that depends on the details of the raindrop’s acceleration to terminal velocity. When the pressure wave first hits the ground it reflects, and you have to add in the reflected wave as if from a mirror image of the raindrop rising below the ground.

I probably ought to add that the above discussion makes various simplifying assumptions, like that the Reynolds number is small, which requires small droplets. Check the usual mathematical conditions on Stokes flow to be safe.

NiV, by “There is, however, no hydrostatic surface effect once the particles reach terminal velocity.” it is meant (at least I so understand) that pressure at the surface does not equal the initial column weight. (So it is in a way in disagreement with your statement.) In their Fig. 8 surface pressure when rainfall is present after an initial ~1sec jerky behaviour, is reduced to a value approximately equal to that of the final state (when droplets have fallen down). I.e. surface pressure drops immediately and never returns to the initial value despite it takes quite some time for the droplets to fall out (at 5 m/sec from a few km height).

“The pattern of pressure changes on the ground will be more complicated, although it will still have to integrate up to the weight of the raindrop.”
Concerning the waves from the droplet, given that the droplet moves slowly compared to the speed of sound, the weight of the droplet (i.e. its dynamic presence) should be spread over a fairly large area.

When the droplets fall at constant velocity they contribute by their whole weight to the mass of the atmosphere and pressure at lower altitudes. Only, when they are accelerating is the contribution less. Anything else contradicts the Newtons’s law.

‘winds are driven by pressure gradients’ (comment by Anastassia Makarieva 1 Feb, 12:29am) or ‘kinetic energy generated by horizontal pressure gradients’ (main post) – I’m not so sure of that. Are not the winds ultimately driven by temperature gradients (horizontal and vertical) and the rotation of the earth? It is the movement of the air (the winds) that produces horizontal pressure gradients.

For example, the movement of the air produces low pressure systems. Not the other way round, despite the common habit in for example weather forecasts of claiming that tightly packed isobars are the cause of the strong winds with which they are associated.

But water in all its phases, and of course the transitions amongst them, is clearly very important in the climate system, and so as an interested bystander I am very glad to see this paper as evidence, I hope, of lively research in this area. The amount of attention that has been paid to carbon dioxide in recent decades (especially in politics!) seems to me out of all proportion to its importance in the system compared to, for example and perhaps especially, water.

John Shade | February 3, 2013 at 7:51 am | ‘winds are driven by pressure gradients’ (comment by Anastassia Makarieva 1 Feb, 12:29am) or ‘kinetic energy generated by horizontal pressure gradients’ (main post) – I’m not so sure of that. Are not the winds ultimately driven by temperature gradients (horizontal and vertical) and the rotation of the earth? It is the movement of the air (the winds) that produces horizontal pressure gradients.

For example, the movement of the air produces low pressure systems. Not the other way round, despite the common habit in for example weather forecasts of claiming that tightly packed isobars are the cause of the strong winds with which they are associated.

Thank you for pointing that out. I’ve now had a look at a few more explanations and it appears that winds created by temperature differentials are marginalised and one of its effects has been made the driver, pressure differences. What I had previously taken as being a poor explanation seems to be the now the usual telling.

Though quite what it means by the following is anybody’s guess: “The greater the mass of air above us, the higher the pressure we feel, and vice-versa. The importance of this is that air at the surface will want to move from high to low pressure to equalise the difference, which is what we know as wind.”

What puzzled me, Anastassia, is Section 3.3 of your paper, with the two columns. It says:

“Water vapor in column A is saturated at the surface (i.e., at z = 0) but non-saturated above it (at z > 0). The saturated partial pressure of water vapor at the surface pv(Ts) (4) is determined by surface temperature and, as it is in hydrostatic equilibrium, equals the weight of water vapor in the static column.”

As far as I know, this last sentence cannot be true: it would mean that the weight of water vapor in the static column would be fixed by surface temperature, and vice versa. I was taught that the partial pressure of water vapor is just (by a good approximation) the (local) molar fraction times the total pressure.

Then (24), (26) for a saturated column are ok as far as I can judge. But the problem with the interpretation of pv(Ts) above comes back in (27): pv(Ts) is not the original weight of water vapor in the static column. In (27), it should be replaced by the integral of g times the initial water vapor density, which was not specified except that it was unsaturated except at the surface.

This is where I got stuck. I suppose it is an important issue for the suggested mechanism, i.e. the explanation of figure 1(c).

I was taught that the partial pressure of water vapor is just (by a good approximation) the (local) molar fraction times the total pressure.

Thank you for your question. What you were taught is correct for a usual atmospheric column with a non-zero lapse rate. In such a column molar fraction of water vapor decreases with height. In our thought experiment both columns are initially vertically isothermal (see p. 1042). I.e. temperature does not decrease with height. Then water vapor follows the hydrostatic distribution and its total amount in the column is determined by surface temperature.

” In our thought experiment both columns are initially vertically isothermal (see p. 1042). I.e. temperature does not decrease with height. Then water vapor follows the hydrostatic distribution and its total amount in the column is determined by surface temperature.”

It won’t retain that distribution for long. An atmosphere, by definition, is unstable whenever the environmental lapse rate is below the saturated lapse rate. Zero lapse rate is far below saturated (wet) lapse rate. There will be a buttload of vertical motion in that atmosphere until it becomes at least neutral which, again by definition, is an environmental lapse rate somewhere between wet and dry lapse rates.

A totally isolated column of gas under gravitation in equilibrium is isothermal and each type of molecules has its own exponential density profile. The coefficient of the exponential is proportional to the molecular weight. Thus the molar fraction of water vapor would increase with altitude.

In my view it does not, however, make any sense to consider at all an isothermal column to start with, and even less sense to consider a column with such molecular density profiles.

It does not make sense to calculate the difference between the equilibrium that can never be even approached and a realistic stationary state. They find a large difference between these two profiles and imply that such large values would be significant for the physics of the atmosphere. That’s, however, totally false. The equilibrium state is totally irrelevant for real physics and calculating deviations from that is pure nonsense.

That isothermal column is I believe a thought experiment. Since there is a lapse rate, the actual column of air could not be isothermal. An isothermal layer in that column can form and expand upward and outward in a ratio limited by available water vapor. The horizontal expansion would have to be greater than the vertical expansion if the layer were stable.

Pekka, “It’s not only a thought experiment. They calculate deviations from that and draw strong conclusions from those deviations. That’s, what’s so crazy.”

Hey, I am fluent in crazy. Using the thought experiment just provides a limit of the potential energy. The condensation “lens?” can only expand so far vertically, so the “spread” in the horizontal would be necessarily much larger with the total limited by the ideal potential energy.

How they worded that, if that is what they were doing, sucks, but I can see using it the way they did.

“A totally isolated column of gas under gravitation in equilibrium is isothermal”

That’s. Internal energy of a mole of gas at any give altitude is identical in a non-convecting atmosphere. Temperature is not identical measured with a thermometer as a thermometer measures kinetic energy while internal energy is the sum of kinetic and gravitational potential energy.

You should know better. A isothermal atmosphere in equilibrium is a physical impossibility. A contradiction in terms.

Go forward and backward from the page above. It begins with the formula to integrate upward from the surface for column internal energy. In an equilibrium column internal energy of a mole of gas is the same everywhere. The volume which contains the mole is what varies and the temperature varies by the change in volume according to (among other ways of obtaining it) the ideal gas law.

Until you wrap your head around the concept that thermometers don’t measure internal energy you will be a source of confusion to both yourself and others.

You are wrong. Gravitational energy does not enter in the temperature in a convective atmosphere.

The average gravitational energy is temperature dependent in an isothermal atmosphere of thermal equilibrium. In other words the average altitude of the molecules depends on the temperature of an isothermal atmosphere. That’s how the equipartition theorem applies to gravitational energy.

@DW: It makes just as much sense as the zero feedback equillibrium sensitivity to CO2 doubling, which some people think is very important.

Touché.

At the 1930 Solvay meeting Einstein proposed a thought experiment purporting to defeat Heisenberg uncertainty by opening the shutter of a box arbitrarily briefly to allow a photon to escape at an accurately known time then measuring the resulting decrease m in weight of the whole box to arbitrary accuracy so as to estimate the photon’s energy E accurately as mc^2.

For a photon of visible light m would be about 0.000005 times the mass of an electron, a minor experimental detail that apparently didn’t bother Einstein.

Actually the tropopause is by definition vertically isothermal (if only over a kilometer or so) so it’s not purely theoretical. And it should be possible to measure zero feedback equilibrium climate sensitivity on a small scale if not on a planetary one.

Pratt, an isothermal column is extremely unstable with a buttload of vertical motion.

Pirila, I pointed you to the appropriate chapter at Murray Salby’s book on atmospheric physics. I can lead a horse to water but cannot make him drink. Gravitational potential energy is a component of internal energy. Internal energy is used in many formula that deal with the atmosphere. This is explained in the atmospherics physics chapter I pointed out to you. If you think it not true then I suggest you go argue with Salby not me.

@David X (where X on this blog is never “Mermin”, sadly): An isothermal atmosphere at equilibrium is a contradiction in terms. The fully relaxed state is maximum entropy and that is acheived when internal energy, not temperature, is equal everywhere.

Can you (emphasis on you) prove that the presence of any field (gravitational, electrostatic, or whatever you like) can create a situation where internal energy is equal everywhere even though the temperature is not?

If you can’t do it yourself then you’ve probably just misunderstood something you read somewhere.

Given a completely closed vertical column of air in a gravitational field, closed in the sense that no energy enters or leaves it, the equilibrium state towards which it will drift (very slowly) is an isothermal one. The drifting is slow because diffusion is the only mechanism by which temperature can change.

This would not be the case if the condition ELR < ALR resulted in unstable air as you seem to believe. However you have that condition backwards: ELR < ALR is absolutely stable. This includes the isothermal case ELR = 0. There can therefore be no convection, leaving diffusion as the only remaining transport mechanism.

Pekka and Vaughan, I have to side with David Springer here. A well-mixed atmosphere in gravity is in a state known as isentropic where the potential temperature is uniform. This is the dry adiabatic lapse rate. If you take an isothermal gas in gravity and thoroughly mix it, it turns isentropic. On the other hand, an isothermal atmosphere is a stable state and won’t mix spontaneously unless you stir it by some means, but that is true of all stratified states, not just isothermal, but temperature inversions that are even more stable. The dry adiabatic lapse rate is the maximum entropy state which is achieved by mixing until it is homogeneous in the potential temperature. With no gravity this would be isothermal too.

There’s no question about the fact that an atmosphere with vertical convection has a lapse rate that’s adiabatic lapse rate, moist adiabatic lapse rate, or something called environmental lapse rate depending the particular conditions. No disagreement on that.

That kind of atmosphere is, however, not isentropic or in thermodynamic equilibrium. It’s typically in a stationary state, but never a thermodynamic equilibrium. In thermodynamic equilibrium the atmosphere is isothermal and the vertical profiles of each type of molecule have their own exponential dependencies with altitude. An atmosphere in thermodynamic equilibrium is stratified and totally free of vertical convection and mixing. The only vertical motion is diffusion at molecular level.

Whether any atmosphere anywhere is in thermodynamic equilibrium is questionable (answer is almost certainly that no atmosphere is in thermodynamic equilibrium), but that does not change the properties of a thermodynamic equilibrium.

Pekka, thermodynamic equilibrium is not a well defined concept to me. Radiative equilibrium does drive towards an isothermal state, but mixing goes towards an isentropic state, which is a recognized term indicating constant potential temperature (also dry adiabatic) because the log of potential temperature is basically the entropy in thermodynamic terms.

Thermodynamic equilibrium in gravity is different from that in no gravity. They lead to different pressure profiles and hence temperature profiles. As a term, it is too vague to define the profile by itself.

It’s equally well defined with gravity. it’s isothermal also with gravity. The densities drop exponentially for every species of molecule at a rate given by molecular weight. The average gravitational potential energy of every molecular species is given by equipartition theorem as kT/2 per molecule.

Pekka, no the potential energy starts to matter. Velocities of molecules tend to be lower at higher altitudes (cp*T+g*z is roughly preserved because Vdp=~-g*dz). As air ascends it encounters lower pressure, expands and cools. A truly mixed state is adiabatic. Once air gets into that state it cannot settle out into another profile (or unmix) because that maximizes entropy.

They are not slower at higher altitudes. Gravity affects the density, but it does in such a way that the velocity distribution is the same at all altitudes. Molecules that are slow have a higher probability of falling than rising, while faster may also rise higher. Going through all that in detail proves that everything fits perfectly together.

Pekka, I don’t think you are disputing that in an adiabatic convective profile, the temperature at higher altitudes is colder, so the higher molecules are slower, and are continually moving up and down without losing or gaining diabatic energy but with their temperature changing, so I think this argument is about whether the convective profile is an equilibrium profile or not. I say it is, except for conditions where the equilibrium is controlled by radiation, which is a diabatic process.

Convective atmosphere is a totally different case. In the Earth atmosphere the situation is closer to what I have been talking about at altitudes of well more than 100 km, i.e. outside the turbopause. Up to the turbopause convective mixing dominates, above turbopause we have diffusion and an atmosphere that has many properties of thermodynamic equilibrium. In particular the density profiles are there different for each molecular species.

Coming back to the troposphere. The temperature drops with altitude, because in convection molecules do not move individually and are not subject to the automatic selection that favors faster molecules in upwards diffusion. Most importantly a rising parcel of air does work in pushing other air out of the expanding volume.

Adiabatic expansion causes cooling also without any rising movement. That’s used in some heat pumps although heat pumps are usually based on phase transition, because that leads to better efficiency.

Jim, a very simple way to show you’re right is to consider the case of a single air molecule bouncing perfectly elastically up and down on the surface, with enough energy to bounce say 20 km high. Clearly it will be moving faster in the lower half than the upper, and therefore will have more energy in the lower half.

It follows that a gazillion molecules doing this in a column, perfectly vertically without ever colliding with each other, would produce a column of air which is hotter in the lower half than the upper. QED

Unfortunately this simple proof has one little flaw: population.

Each molecule traverses the same distance in the upper half as in the lower, but more slowly. Hence it spends more time in the upper half than the lower. So even though each one is contributing more thermal energy to the lower half than the upper while it’s there, there are more molecules in the upper half at any given instant which tends to offset that effect.

If a plate is placed over the column so that molecules bounce off it before reaching their peak, it doesn’t change this overall story. What it does show however is that pressure is behaving “normally” because the force exerted on the surface by the molecules bouncing off it is much greater than that on the plate above. It also shows that lower pressure need not entail fewer molecules per unit volume.

While this isn’t intended as a replacement for Pekka’s rigorous proof (for one thing the absence of collisions makes this far from an ideal gas so PV = nRT doesn’t hold at all), it might help to undermine at least a little the refutation of Pekka’s proof that you may have had in mind.

Vaughan and Pekka, I am not going to be convinced by non-interacting molecules because that lacks the pressure effect of collisions. Anyway defining thermodynamic equilibrium states is beside the point to me, so I won’t pursue this further here.
I think we agree that this paper and the descriptions of processes here by the authors are designed to leave us in doubt that latent heat really does lead to increased buoyancy and that buoyancy really does lead to ascent. If they wrote a paper focusing on these two points, it would be very entertaining to see how it does in the review process, because this is as much a departure from reality as their contrarian condensational pressure reduction idea.

No need to discuss the thermodynamic equilibrium further. Related to your message I do, however, note that intermolecular collisions don’t change the pressure of an ideal gas.

Collisions are needed to maintain local thermal equilibrium, but the pressure is independent on their frequency. The local thermal equilibrium is in many ways essential, while the global thermal equilibrium is not. Collisions are certainly involved in all pressure effects but even mutually noninteracting molecules would exert the same pressure on surfaces, if they could somehow be brought to the state with the Maxwell-Boltzmann distribution of velocities.

The interactions between the molecules have a small influence on pressure when it’s necessary to apply real gas equations of state like the van der Waals equation That’s not necessary in atmospheric considerations.

“It follows that a gazillion molecules doing this in a column, perfectly vertically without ever colliding with each other, would produce a column of air which is hotter in the lower half than the upper. QED

Unfortunately this simple proof has one little flaw: population.

Each molecule traverses the same distance in the upper half as in the lower, but more slowly. Hence it spends more time in the upper half than the lower. So even though each one is contributing more thermal energy to the lower half than the upper while it’s there, there are more molecules in the upper half at any given instant which tends to offset that effect.”

But molecules of gas don’t travel distance. A molecule of gas is constantly being hit by zillions of other molecules and are constantly changing direction. An average single molecule is not going anywhere- not environment where there lots of gas molecules.
So instead of average molecule going bottom of atmosphere up to top in a minute, it’s staying basically in same location for hours or indefinitely.

Or the energy of the kinetic gas is forward, backward, upward, downward,
left, and right and this changing every nanosecond.
It’s only in lower gas density environment where a gas molecule is able to travel any significant distance, because you could say “the many” determine a single molecules direction- and when in environment there fewer molecules, the velocity of single average molecules is able to travel any amount of distance.

So the lower and density atmosphere is like a huge traffic jam- once molecule enters “it’s never going to get anywhere”.

Vaughan noted that the idea was not to prove anything but to make it little more understandable that the equilibrium is isothermal. The same is true for the paper that I linked in this thread. The authors tell there as well that the purpose is to help understanding, not prove.

The note that I have written and also linked further up in this thread has a different goal. It presents a proof that kinetic theory of ideal gases under gravity has an isothermal equilibrium. Being a proof it’s certainly more difficult to understand. It does not assume that the molecules don’t interact but takes molecular collisions into account.

Vaughan noted that the idea was not to prove anything but to make it little more understandable that the equilibrium is isothermal. The same is true for the paper that I linked in this thread. The authors tell there as well that the purpose is to help understanding, not prove.”

I don’t think atmosphere is a equilibrium isothermal. At least per this definition of:
“The state of an atmosphere at rest, uninfluenced by any external agency, in which the conduction of heat from one part to another has produced, after a sufficient length of time, a uniform temperature throughout its entire mass. Also known as conductive equilibrium. ”

Now atmosphere at rest is strange idea considering the molecules bouncing about at 1000 mph.
But I am assuming what meant is there isn’t excessive heating or cooling and it’s not windy and there not all kinds of stuff going on [also generally known as weather- so “normal” and calm weather].
I would agree it’s same heat, if allowing for PE as equaling heat/energy.
So, the equilibrium one discussing is a balance of heat, if this balance of heat included potential energy of molecules at higher point in the gravity [what Vaughan described].
The problem I had with Vaughan is he said the molecules which converted the PE into kinetic energy [by falling- and kinetic energy in regards to gas *is* heat] would spend less time in a lower part of atmosphere because they traveling a further distance in shorter period of time.
Which is correct IF you bounce the molecules without inference from other gas molecules with different vectors. And if this was the case then the gas molecule at the lower of the atmosphere would have higher kinetic energy BUT because there was very few of them in a given volume [most time they would at a higher elevation] so far less mass is involved.and the gas would actually have less heat [though btw, the surface would have to be very warm otherwise the high velocity gas molecules would transfer their energy to the surface {they would not bounce perfectly, it would more like a bug spat against a windshield}].

If invert what Vaughan is talking about, it’s describing the stratosphere and higher. Where there less molecules and so less inference to distance traveled by a molecule. Or instead inverting, just consider the top of troposphere as the “surface”- it’s a spongey surface but is hard enough to faster moving molecules- and faster molecules are “selected” by the process.
Though both apply.

But in the troposphere the gas molecules are stuck in a mad traffic jam. And one could say the lapse rate is one type of measurement of this traffic jam. With the water molecules as quite significant in terms of bogging down the traffic.

My statement on the irrelevance of the thermodynamic equilibrium referred to the full atmosphere, which is always far from the thermodynamic equilibrium. Thermodynamic equilibrium is a very useful and important concept for many other systems including local thermodynamic equilibrium of small volumes within the atmosphere.

The condensation temperature should be the “surface” at saturation. Below that layer would be supersaturated air and above would be near saturated air.

That would create a small pressure differential creating a circulation that would expand the “surface”. What is actually happening with the energy would require more work and it is a bit of a chicken or egg situation as to what starts the process, but that small differential could build if the conditions are right.

Pekka, “It’s just another case where formally correct mathematics is used to derive wrong physical conclusions.”

Likely, but that may be partially due to the formally correct models. Saturation pressure is dependent only on temperature, based on the models, leading to these nasty little situations like super saturation and having to assume things because the models don’t model them very well.

The detail that makes the calculation so meaningless is the comparison with the isothermal full thermodynamic equilibrium with the molecule specific density profiles. That’s so extremely remote of anything really occurring in the atmosphere that it produces totally spurious large differences.

pekka, “The detail that makes the calculation so meaningless is the comparison with the isothermal full thermodynamic equilibrium with the molecule specific density profiles.

Isothermal in the x direction and equilibrium in the z direction in a thin layer at the temperature of condensation which is set by surface temperature since “surface” temperature is the basis for estimating saturation vapor pressure.

It is circular because the references for saturation pressure vary with the freezing and boiling point of water that would vary with sea level and composition of the gas if I read the equations correctly.

Their state of comparison for their moist column is fully isothermal. The water content is chosen to be at saturation at the surface. The saturation partial pressure depends only on temperature, not on anything else. With increasing altitude the partial pressure of water goes down but the share goes up, because the partial pressure of dry air goes down faster.

That’s all true for the thermodynamic equilibrium. That’s, however, irrelevant because the real atmosphere is always very far from thermodynamic equilibrium both in it’s temperature profile and in maintaining essentially constant stoichiometry for all noncondensible constituents. Water vapor is different in that and its share varies widely.

As I wrote the calculation of the isothermal column is mathematically correct. What’s wrong is to use it in comparisons in the way they do. Any comparison can, of course, be made, but this kind of comparisons do not tell anything worthwhile. They do, however, claim that the comparison tells things that it most certainly does not tell. Their physics is totally wrong.

Pekka, “As I wrote the calculation of the isothermal column is mathematically correct. What’s wrong is to use it in comparisons in the way they do.”

I agree completely with that. The actually “effect” they are implying is real and the delta P based on saturation vapor pressure provides sufficient potential energy to allow a “new” approach. The devil is in the details.

“I think that it might be productive for you to decide whether you want to persuade your readers in a mathematical or a physical fallacy present in our paper. It is easy to see that you cannot have both, so this takes away from the strength of your critique.”

Not at all. The physics fallacy is believing the new equation (34) is based on physics other than mass conservation. You have often claimed that, but never said what that other physics is.

But the math fallacy is then using it as an independent equation. You already have sufficient equations in Eq 32 and 33. Eq 33 determines S. You then add Eq 34 as another equation in the same variables as 32 and 33. The system is overdetermined.

The last statement is a good and strong mathematical claim. Had you been able to prove it, the paper would have been rejected. This is my view. But the problem is that you did try a few times, but had not been successful — despite your ubiquitous claims to the contrary.

For example, you say today that (33) determines S and (34) also determines S. Let us take a look if this is indeed so.

(32) is an equation on ∂N_d/∂x and ∂N_d/∂z (N_d is dry air molar density).
(33) is an equation on ∂N_v/∂x, ∂N_v/∂z and S (N_v is vapor molar density and S is condensation rate)
(34) is an equation on ∂N_d/∂z and ∂N_v/∂z and S.
We additionally have ∂N_v/∂x = 0 (horizontally isothermal atmosphere).

So, we have five formal variables: ∂N_v/∂x, ∂N_v/∂z, ∂N_d/∂x and ∂N_d/∂z and S. And we have four equations. This means that if we are lucky and know S, we can possibly express any other variable as a function of S.

Now you say:

Proceeding from there just leads to nonsense results. For example, I noted that if you combine Eq 34 with 36, you get S=u∂N/∂z.

You must have made a typo here, the correct expression is S=u∂N/∂x = u∂N_d/∂x.

But please appreciate that mathematically this is no nonsense. It is exactly what we have been hoping for: to express one of the variables in terms of S. And we did it. This is a valid mathematical result.

To support your claim of a mathematical fallacy, you would have needed to demonstrate that the system (32)-(34) produces a mathematical contradiction. E.g. y = x AND at the same time y = x/2, you know. This is what overdetermination is about. For example, in your comment above you attempted precisely that: you claimed that our equation (A7) formally contradicts (34). But that was an erroneous statement of yours.

So, I would still propose that you should focus on a physical fallacy, it is a much more foggy business. This is what you are actually doing:

Proceeding from there just leads to nonsense results. For example, I noted that if you combine Eq 34 with 36, you get S=u∂N/∂z. That is, precipitation rate is equal to a wind velocity component times an air density gradient. This doesn’t require the presence of water at all. Rain out of dry air!

Please appreciate that mathematics does not know what rain is. It is indifferent. Your claim is purely physical, and the alleged “nonsense” that you are proposing is physical as well. I’ll address your physical proposition separately. It is interesting!

Anastassia Makarieva asserts: “So, we have five formal variables: ∂N_v/∂x, ∂N_v/∂z, ∂N_d/∂x and ∂N_d/∂z and S. And we have four equations. This means that if we are lucky and know S, we can possibly express any other variable as a function of S.”

Anastassia Makarieva, this statement makes grammatical sense, but it does not make mathematical sense! The reason is that (e.g.) ∂N_v/∂x and ∂N_v/∂z must satisfy an integrability condition (because otherwise N_v(x,z) does not exist globally, even though ∂N_v/∂x and ∂N_v/∂z are locally well-defined locally) and thus ∂N_v/∂x and ∂N_v/∂z cannot consistently be regarded as independent variables.

It is concerning that within both the long-active (but not-yet-accepted) “PSI” community and the nascent (but not-yet-accepted) “condensation-driven winds” community, foggy verbal arguments commonly are prefaced with imprecise (and/or just plain wrong!) mathematical statements.

Donald Knuth says: “Science is what we understand well enough to explain to a computer. Art is everything else we do. […] Science advances whenever an Art becomes a Science. And the state of the Art advances too, because people always leap into new territory once they have understood more about the old.”

Verdict By Donald Knuth’s criterion, both PSI-theory and condensation-theory presently qualify as “Art”, but not as “Science”. So after repairing their mathematics, both PSI-theorists and condensation-theorists should verify the repaired mathematics by providing some sample code!

Donald Knuth says: “Science is what we understand well enough to explain to a computer. Art is everything else we do. […] Science advances whenever an Art becomes a Science. And the state of the Art advances too, because people always leap into new territory once they have understood more about the old.”

Almost prophetic. A lot of experimental and practical genetics is now done in laboraties the size of an integrated circuit chip where reaction sites are microscopic wells numbering in the thousands replacing test tubes, electrical currents shuffle stuff around the initial and resultant reactants, lasers read the results, and a computer controls it all.

Moore’s Law evidently applies to synthetic biology. Write that down, Sidles, you’re going to need to know it in the future.

And by the way, Knuth is wrong. When you can explain it to a computer it becomes engineering not science. We are just at the beginning of explaining biology to a computer but biology has been a science for centuries. It was perhaps still art when Da Vinci was dissecting bodies and making drawings of human anatomy but I’d argue it was science then too.

And in climate science, the same accelerating reliance upon computation is a plain fact-of-life, eh?

Many wet-bench biologists are distressed to hear 21st century graduate students proclaim “Experiments are for robots!” More broadly, it commonly happens 20th century scientists and engineers — who are not themselves overly possessed of mathematical maturity — are discomfited that 21st century scientific careers require mathematical maturity absolutely.

In your argument for Eq 34, you ignored horizontal velocity and horizontal derivatives. I think that needs to be justified, but doing it yields, from 32 and 33:
S=w(∂N_v/∂z – N_v/N_d ∂N_d/∂z)

The only difference from 34 is the appearance of N_d instead of N. This reflects your error of using N (moist air) as the non-condensable reference gas rather than N_d.

So Eq 34 does not represent new physics. It represents 32 and 33, with the added term N_v/N ∂N/∂z – N_v/N_d ∂N_d/∂z. This is purely due to error. But the effect of treating 34 as an extra equation is to add the equation
N_v/N ∂N/∂z = N_v/N_d ∂N_d/∂z
to your reasoning chain.

Well, almost. The horizontal components that were ignored all come in to this difference equation too. But you have added a new equation that makes no physical sense whatever.

The equation (34) is, indeed, strange. As you point, the first part of that can be derived from (32) and (33) except that instead of N we have N_d and that the derivatives with respect to x must be set to zero.

This get really bizarre when these equations are used to derive a formula for partial derivative of p with respect to x. Dropping x -dependence out in (34) it was effectively stated that nothing relevant depends on x. How can anyone imagine that an equation based on such an assumption is used in deriving the dependence of one related variable on x. How can they assume that the partial derivative dN_v/dx=0 when the partial derivative dp/dx is not zero as the latter would clearly imply also that T varies horizontally.

It’s also true that claiming that S is given by both (33) and (34) is not justified and is hardly justifiable and that all the equations (32), (33) and (34) are used to derive the next equations.

Previously I thought that they do the mathematics correctly and err only on physics, but evidently they mess totally the mathematics as well.

Pekka,
“Dropping x -dependence out in (34) it was effectively stated that nothing relevant depends on x.”
Yes. I think what has happened is that the argument for Eq 34 was made in a vertical updraft situation where it may be that those horizontal terms were negligible relative to the vertical terms retained. But the effect of the overdetermination is that these terme are asserted to be equal to the error-induced term as an equation, which then gets applied everywhere. I now realize that even without the incorrect use of N as the noncondensable reference, the discrepancy in treatment of the horizontal parts alone would have nessed everything up that follows.

Nick,
Some of my earlier comments have essentially stated that a much more comprehensive analysis is needed before any horizontal derivatives can be estimated at all, because something is needed to set the horizontal scale and other essential relationships between vertical columns.

Anastassia, I think Nick Stokes was right about this:
“This reflects your error of using N (moist air) as the non-condensable reference gas rather than N_d.”

If you replace in your (33) N_v by N_v/N_d, u by N_d*u and v by Nd*v, you get: ∇(N_v/N_d) . (u,v)= S/N_d, which has characteristics
dx/dt= u,
dz/dt= w,
d(N_v/N_d)/dt= S/N_d,

with N_v/N_d= γ/(1-γ)
Now I tend to agree with you about the nature of the “source” term: it should not be seen as an independent physical source term, but simply expresses what should happen according to the relationships in Section 2.1. That means that along the characteristic,
d(N_v/N_d)/dt= w ∂(N_v/N_d)/∂z,
so
S= w N_d ∂(N_v/N_d)/∂z = w N (1-γ) ∂(γ/(1-γ))/∂z
and so you also have your compensation for overall volume expansion right there. I think that is it, nothing new or unphysical. So you are right, your equations in 4.1 are pretty close anyway, but the one above is rigorously derived.

Anastassia,
When it comes to proving mathematical contradiction, I’ll settle for nutty results. And I cited one.

Nick, “nutty results” and “mathematical contradiction” is not the same. “Nutty results” do not make a ground for accusing people of all possible things. Let’s be specific as Steven Mosher wants us to be. You cited two things (if I have not overlooked anything.) Here as I clarified your claim was based on a mathematical error. Here you spoke about rain from dry air, which has nothing to do with mathematics. (I do remember this point, it will not be ignored, just not everything at once).

So, I am glad that you have now concentrated on physics. And you are making progress, you no longer assert that (33) defines S or the system is overdetermined. Your points now is: “But you have added a new equation that makes no physical sense whatever.” Let’s discuss this.

Anastassia,“Nick, “nutty results” and “mathematical contradiction” is not the same”
Well, if that semantics is important to you, let’s deal with the nutty results. I said that because of the lack of independence of 34 from 32 and 33, you had introduced an equation which asserted that the discrepancies were exactly zero, without justification. I see this is now made explicit – that equation is A7. (Sd-S) is the measure of the difference made by choosing N as the reference gas density rather than N_d. And the left side, u ∂N/∂x, is one of the terms you omitted in forming 34, but was present in 32/33. The others seem to be omitted by your maintaining the requirement that ∂N_v/∂x=0.

So if you had S=S_d, you would have u ∂N/∂x =0. But you also has this equal to S. So S=0? It never rains but it pours from dry air?

For more weirdness, try putting real values of C, the kinetic constant, into A10.

After a little more thought, it still seems to me that the sign in eq. (27) is wrong:
h_v(z’)<= h_v(0) (see fig. 1(a)),
therefore exact rho_v(z) <= approximate rho_v(z) (as it is an increasing function of h_v(z') in (26)),
and therefore, the right-hand side of (27) should be a lower bound to the change in surface pressure rather than an upper bound as stated.
That makes the approximation of p_A(z) in (30) a lower bound, so the pressure difference p_A(z)-p_B(z) may as well be 0 at the surface. It does not need to be negative.
Or am overlooking something?

What you are saying concerning the heights is correct. But as one can see from Fig. 1b, delta ps is defined to be a positive value. I.e., its absolute magnitude is shown and calculated in Eq. (27): delta ps ≡ -(p_A(0) – p_B(0)).

That is right, just wanted to write that, so that actually helps :). So your point of the approximation is that the adjustment process from isothermal to adiabatic profile leads to a drop in surface pressure in the saturated column, and not in the dry column, if you keep the surface temperatures the same.
I guess this initial condition is rather remote from the final state; what does a change in column weight between these states then mean, since in the beginning, there was far more water vapor present than would be realistic? Is it relevant for what happens in the real atmosphere?

As people seem to be discussing Section 3.3 “Pressure profiles in moist versus dry air columns”, I would like to provide some hopefully relevant context. In this Section a thought experiment is considered to illustrate the basic ideas and scales at work. A vertically isothermal column with vapor saturated at the surface (A) or dry air (B) is cooled such that it acquires either a moist (A) or a dry (B) lapse rate. The main purpose of this excercise is to illustrate that, because of condensation, surface pressure in column A will be lower (Fig. 1c) than in column B, while in the upper atmosphere the reverse will be true (because of the difference in the dry and moist lapse rate).

One might think — why would they need it? In fact, with this excercise we were responding to our previous influential critics (like, e.g., Dr. Rosenfeld) who denied the very opportunity that there can be a pressure fall associated with condensation. Now everybody seems to know that, but at those times things were different, and the issue was not clear to many.

That this is an objective vision of the situation is supported by the fact that approximately during the same time that our paper was submitted to ACPD (but after it was posted at arxiv.org), Spengler et al. (2011) undertook an effort that was in some way similar.

Spengler et al. (2011) did the following: they took a normal column of air with an observable quantity of the water vapor and then imagined, in a thought experiment, that all vapor between 2 and 4 km in the atmosphere suddenly condenses, the latent heat is released in the sensible form and warms the atmosphere. (So people believing that our thought experiment is far from reality should see that in an appropriate context). They investigated how the hydrostatic equilibrium sets in and found that indeed, the surface pressure drops, while the upper atmospheric pressure rises (because of warming). This result of Spengler et al. (2011) basically repeats what is shown in Fig. 1c.

I think that the work of Spengler et al. (2011) was interesting. However, Spengler et al. (2011) from their 1-D thought experiment drew far reaching conclusions about the unimportance of the condensation-related pressure drop. This cannot be done in principle for a 1-D case. Unlike Spengler et al. (2011), we used our thought experiment in Section 3.3 solely to illustrate the involved physical concepts and scales. The real-world horizontal pressure gradients that are produced by condensation are considered in Section 4.

I note the work of Spengler et al. (2011) here because it was mentioned by Dr. Held in his review as an evidence against our propositions. Besides being for 1-D case, the process considered by Spengler et al. (2011) represents adiabatic condensation at constant volume that we showed in Section 2.1 is not physically possible.

The real single process of interest to the issue that you study seems to be that of ascending air, where

– evaporation brings moisture into the air and the temperature is set to a specific value. The density is affected by both temperature and moisture level
– the air ascends. At some point (possibly immediately) the relative moisture reaches 100% and condensation begins.
– the condensation is a continuous process that goes on as long as the air ascends
– in condensation latent heat is released and water is removed from gas phase to liquid droplets (or at some point ice)
– under proper conditions the process is nearly adiabatic. If this is the case the resulting temperature profile follows the moist adiabatic.
– under conditions that lead to adiabatic transition the pressure is also very close to hydrostatic pressure at every moment and every altitude
– the loss of water from the air does not affect the pressure, it reduces the volume of the remaining air
– the speed of the convective flow is reduced due to the reduced volume of the gas.

When I wrote “does not affect the pressure” I meant the local process. The moist adiabat calculated taking the chances in stoichiometry into account differs a little from the approximate values obtained when it’s not taken into account.

The pressure levels depend also on the amount of falling precipitation. To calculate that effect the size of the droplets must be determined as the result depends on the terminal speed of the droplets.

If anything else tries to disturb the temperature (or more accurately energy content) derived from those 3 characteristics alone then all one sees is a change in circulation adjusting the flow of energy throughput to keep top of atmosphere radiative balance stable.

The stabilisation process involves the switching of energy to and fro between KE and gravitational PE and that is what determines temperature since only KE registers on sensors as temperature.

The switching to and fro between KE and PE is achieved by expansion and contraction.

With the caveat that I’m not used to thinking about the water cycle in this detail, so don’t have an easy familiarity with the terms, I’m rather enjoying the discussion – I particularly like the Anastassia/Pekka loggerheads here:

Pekka’s – “the loss of water from the air does not affect the pressure, it reduces the volume of the remaining air”

versus Anastassia’s – “Spengler et al. (2011) did the following: they took a normal column of air with an observable quantity of the water vapor and then imagined, in a thought experiment, that all vapor between 2 and 4 km in the atmosphere suddenly condenses, the latent heat is released in the sensible form and warms the atmosphere. (So people believing that our thought experiment is far from reality should see that in an appropriate context). They investigated how the hydrostatic equilibrium sets in and found that indeed, the surface pressure drops, while the upper atmospheric pressure rises (because of warming). This result of Spengler et al. (2011) basically repeats what is shown in Fig. 1c.”

So, should be grateful if any replies, from anyone, are couched in least technical language possible..

If the loss of water from the air (condensation) reduces the volume, then isn’t it also increasing the density? If the greater the density the heavier the air wouldn’t that mean pressure increased?

Which is why I can’t get my head around condensation creating an area of low pressure at the surface.

Is condensation the point of change between low and high pressure?

It seems to me that the low pressure at the surface created by the expansion of rising gases would begin to alter at whatever height there was condensation, so while it may appear to still be low pressure at the surface this is about to change as condensation gets into its stride and the colder air around the condensation will also be getting heavier. (The air heated by condensation will continue to rise, but there can’t be ‘vacuum’ around the condensation, the colder air at that level will come in to replace any lighter hotter air rising, and colder is heavier so will sink which increases the pressure at the surface.)

SM Feb 3 @4.07pm on falsifiable statements.
Yeah, Steven, me and the blokes down at the pub would have
a problem with Quine’s arguments about synonyms, distinctions
leading as they do ter ter skepticism about meaning.

Regardless of Quine’s perception of transferring meaning of
synonyms, me and the blokes down at the pub take a statement
ter be ‘true’ *if it has no internal logical inconsistencies and * if it corresponds to the reality, ie the statement: ‘all birds have feathers,’
( or ‘all swans are white,) is true, if, and only if, it corresponds ter
reality. It should therefore be empirically falsifiable.

As we see it, SM, (me and t b d a t p ) yr theory concerning unicorns
and the wind can only be true if and only if the pesky little critters exist . Finnding them … “#!^*#WTF !” would not be confirmation of yr theory
but only give yer a basis fer proceeding,

Beth, you need to go back to carnap. and that does not mean a rest in the in your volvo. Truth as correspondence, is an entirely different matter but never mind I can make do… You surely dont mean that for something to be true it has to be empirically falsifiable.
is the statement “for something to be true it must be empirically falsifiable’ true? that is, is it empirically falsifiable?
Opps. so you just made a statement that contains no logical inconsistencies and which cannot be falsified by empirical evidence. Opps. So, if it is true, then it is false. Opps. thats a paradox fer ya. Ya might consider that a bunch of folks waay smarter have been strugglin with the problems of truth and meaning and if the answer was simple, well, it would be simple.

I think there are several levels to the basic question “Is the proof correct?”:

1. Does Deolalikar’s proof, after only minor changes, give a proof that P NP?

2. Does Deolalikar’s proof, after major changes, give a proof that P NP?

3. Does the general proof strategy of Deolalikar (exploiting independence properties in random -SAT or similar structures) have any hope at all of establishing non-trivial complexity separation results?

After all the collective efforts seen here and elsewhere, it now appears (though it is perhaps still not absolutely definitive) that the answer to #1 is “No” (as seen for instance in the issues documented in the wiki), and the best answer to #2 we currently have is “Probably not, unless substantial new ideas are added.” But I think the question #3 is still not completely resolved, and still worth pursuing (though not at the hectic internet speed of the last few days.)

In other, more mundane words, Tao is trying to preserve what’s good in that venture. If he’s proved wrong, no harm’s done. (He’s Tao, so he’s a bit above it all.) If he’s proved right, no harm done either. Perhaps some embarrassment either way, but no great deal. People are not that interested in others’ failures as much as they fear themselves.

***

There are many questions one may ask about the implications of somebody else’s work. All could be worthwhile. Attitudes must be kept in check, from all sides.

Here’s Lipton conclusion:

Perhaps the last question is what did we learn from the last few hectic days. I think I learned three things: First, that the community is extremely interested in our basic question, P=NP? I find this very positive. I was shocked at the tremendous interest that was generated.

Second, I like that the community reacted in a mostly positive and supportive manner. I think we owe Vinay a thanks, no matter what the final outcome is. He has raised some interesting connections that, as Tao says, may be useful in the future. He also showed how people can ask hard questions, and how the community can be helpful. Yes, there were some tough comments here and elsewhere, but for the most part I think the experience has been positive.

Finally, I realized that it is not possible to keep up the hectic pace of the last few days for much longer. I hope we helped, I hope we were always positive, and I hope the work here in trying to resolve this exciting event has been a positive contribution. I thank you all for your kind interest.

Climateballers should perhaps rejoice that such exciting events became their daily bread. I honestly can’t recall a single week in the last three years that did not include an incident of the magnitude of Deolalikar’s proof. At least, when seen from the Climateballers’ top-of-lungs’ comments.

***

Does every single comment deserve to be played as it was the last two minutes of the Superbowl?

willard, I have been following your comments with interest, and I have been even planning to answer some, but I must confess I do not understand your attitude at all. Perhaps this is because of a different culture, e.g. “the Superbowl” that is so often referred to here does not mean anything important to me.

For example, in this comment, are you pleased or displeased with my response to Nick? I cannot say. Nick has invested a lot of time in criticizing our work and many people draw on his opinion. His reputation will be affected if, after him having proclaimed so many times that our paper is full of mathematical and physical fallacies, people take a closer look and it turns out that it contains new, solid and falsifiable propositions. So Nick can be tempted if unconsciously to exaggerate his claims to prevent people from taking a closer look. (Nobody is free of biases, me neither.) So what I am doing — I am just trying to be as specific as possible not to allow Nick to create confusion in people’s mind. (Hopefully other people including Nick play the same role with respect to myself.) There is no mathematical contradiction in our work and Nick’s claims on this point are unsubstantiated, that’s all I wanted to say.

Also, if we speak of citations, recently I knew the following one. It is from
John Milton, the blind, English poet:

“Give me,” he wrote, “the liberty to know, to utter, and to argue freely according to conscience, above all liberties. Truth was never put to the worse in a free and open encounter… It is not impossible that she [truth] may have more shapes than one… If it come to prohibiting, there is not ought more likely to be prohibited than truth itself, whose first appearance to our eyes bleared and dimmed with prejudice and custom is more unsightly and implausible than many errors… Where there is much desire to learn there of necessity will be much arguing, much writing, many opinions; for opinion in good men is but knowledge in the making.”

To me the main message of this citation (which I do feel is correct) is that when you find something really new, you may not be able at once to find the correct form for this new thing. Should we be writing this paper today, we would have written it differently (mostly like in the post). Many things in our paper I would have today omitted, others I would have re-written — time is going, we are working and the picture becomes clearer together with the arguments. So I am also using this discussion to clarify our points to future readers. It is good to have all arguments discussed in one place — you can later make a list of links to specific comments where important things are discussed.

1. I am both pleased or displeased with your response to Nick. I am pleased it is happening, and displeased it is so difficult to follow. The way the discussion gets fragmented in the thread does not help.

What I feel about the discussion is irrelevant anyway. What matters is that you both clearly exasperated one another. So what you could do, before you go, is to make a final comment, in which you could summarize every point you think should be addressed.

***

2. Most of your comment amounts to what is called, among climateballers and elsewhere, “playing the ref”. You are basically exposing your recriminations against Nick for me to blame him. You are using a strategy that, in transactional analysis, is called “Look How Hard I’ve Tried”.

I’m not an arbitre between you and Nick, Anasstasia. And quite frankly, I could not care less if Nick is wrong or right. Nick can take care of himself.

If you care about what I care, what I would care is that the summary in #1 gets done. I hope you do care about that.

***

3. I don’t think that Nick’s reputation will be affected if your paper “contains new, solid and falsifiable propositions.” Nick is Nick. Nick says what he sees. He can be wrong. If he is, you have to show it to him. He won’t concede anything. But if you do show him, he’ll (perhaps grudgingly) admit it.

Nick’s impersonating what scepticism should be: “believe it, but check it,” as Garry Kasparov always say. When I think about hockey (one of the reason I got interested in climate), I compare Nick’s style to Mario Lemieux, a player not unlike Valeri Kamensky if you can ask around. A one man army. Scores goals all by himself. Likes to play physical, to the expense of his health.

What happens to Nick concerns no one but Nick.

***

4. I have my doubts regarding the cultural difference. Superbowl is quite a big thing in itself. Besides, what I’m talking about is captured by all languages, as Steven Pinker says over there:

> Well, I said I’d talk about two windows on human nature — the cognitive machinery with which we conceptualize the world, and now I’m going to say a few words about the relationship types that govern human social interaction, again, as reflected in language. And I’ll start out with a puzzle, the puzzle of indirect speech acts. Now, I’m sure most of you have seen the movie “Fargo.” And you might remember the scene in which the kidnapper is pulled over by a police officer, is asked to show his driver’s license and holds his wallet out with a 50-dollar bill extending at a slight angle out of the wallet. And he says, “I was just thinking that maybe we could take care of it here in Fargo,” which everyone, including the audience, interprets as a veiled bribe. This kind of indirect speech is rampant in language. For example, in polite requests, if someone says, “If you could pass the guacamole, that would be awesome,” we know exactly what he means, even though that’s a rather bizarre concept being expressed.

Something like this is what happened between me and Douglas at Eli’s first, and then here.

I’ll make this forecast: sooner or later, climateballers we’ll hear from Douglas. He might even become a climateballer himself. I could very well see him blog about your theory, about ecology, big trees, forests, climate models, Einstein, Feynman, Popper, the IPCC. His writing style makes me envision a Lomborgian Honest Broker. An editorial line more enviro-friendly than a rational optimist, but not too far from it. Some concerns. Lots of uncertainty. Models, bad. Anasstasia says. Bad models.

Just a conjecture. We’ll see how it will get falsified.

***

5. Notwithstanding my previous criticisms, I do wish you the best of luck with your theory. Even if this idea you’re cultivating for so many years turns out wrong, at least you’ll have been impassionated by one idea. So many scientists can’t even claim to have had one single original idea. In empirical science, truth is way overrated.

***

6. I’m quite confident that this experience is quite stressful to you. So many criticisms, at so many levels. You just had a taste of Orestes’ predicament:

Making a “list of links to specific comments where important things are discussed” would certainly be a good idea. At the very least, if will provide help you organize the information in a way that can be fruitful and redeeming. You will be able to focus on what’s constructive, and what’s less so. You could even list what kinds of comments tend to “push your buttons”, so to speak, to make sure you are better prepared next time.

7. Yesterday, I tought that the P=NP debate provided a good way to convey what I’m telling you right now. It also conveys the idea that mathematics is not only about formal derivations. It takes time before mathematical proofs become gap-less. Even in mathematics, one can be wrong without being that stupid as to miss a derivation step. It happens.

It is astonishingly obvious that when it rains it storms – that evaporation and condensation is correlated with winds.

If I understand the argument, and perhaps I do not, the paper’s controversial proposal is that evaporation and condensation causes winds and causes the transport of heat to higher altitudes where it gets radiated away.

Which, looking out my window, seems obviously true as an empirical fact. I don’t get strong winds without strong condensation, and when I get strong condensation, things cool down.

This is how the general continuity Eqs. (32) and (33) can be combined:
S = v.( ∇ Nv – Nv/Nd ∇ Nd)
I emphasize that here S is an unknown source term. We do not know, if it is evaporation, condensation, or for example some chemical reaction that changes the amount of water vapor in the atmosphere.

Now we want to find S assuming that S represents — quite specifically! — condensation of water vapor that occurs because of cooling. We consider a steady-state case, so cooling may only happen in a saturated air parcel if it moves to a colder place. From this we propose that S must be proportional to the velocity component that is parallel to temperature gradient. Since our atmosphere is horizontally isothermal, the velocity component that is parallel to temperature gradient is vertical velocity w. Please pause at this moment to appreciate that this statement does not in any way follow from the continuity equation. It is an independent physical statement. At this point we may not even know what the continuity equation might look like at all.

Now, as our process of condensation depends on air motion (NB! it is important, it is an independent physical statement), it must manifest itself in spatial changes of the respective constituent (water vapor). In other words, it should depend on ∂N_v/∂z. (It cannot depend ∂N_v/∂x because we assume a horizontally isothermal atmosphere with ∂N_v/∂x=0). Once again, note at this point that if we were considering, say, a non-steady state with a standstill atmosphere cooling by radiation, then this proposition would not be vaild. We would then need to propose that condensation rate should be proportional to local temperature change rate or something — no grounds to expect it to depend on ∂N_v/∂z. So, I emphasize, at this point we have not anywhere relied on the continuity equation in our argument.

Now we know, again from independent physics, that there is another process that influences water vapor concentration besides condensation: it is gravity. So some part of ∂N_v/∂z is because of the gravitational expansion. We apparently need some reference magnitude to subtract from ∂N_v/∂z in order not to overestimate condensation rate. What can this reference be? (Again, no continuity equation in sight).

We propose to subtract the corresponding share γ= N_v/N of total air density change ∂N/∂z. This is motivated by the argument that we want to identify the effect of gravitational expansion that the air, including water vapor itself(!), undergoes. This gravitational expansion is determined by the hydrostatic equilibrium equation. (You remember, we assume our atmosphere to be hydrostatic). The air as a whole conforms to this equation, while the dry air component does not. This is a very essential point: dry air does not conform to hydrostatic equilibrium, so its molar density changes will not inform us about the effect of gravity.

From all the above considerations, where in no place we have made a recourse to the continuity equation, we write our Eq. (34): S=w(∂N_v/∂z – γ∂N/∂z).

At this point we can recall that there is a continuity equation and check how our expression for condensation rate relates to it. It turns out that (1) Eq. (34) is mathematically independent and (2) that combining Eq. (34) with the continuity equations (32)-(33) produces a meaningful result (37) that conforms to observations and is directly testable from empirical data.

But there is one additional thing we could do. We could check if using dry air as a reference would produce anything meaningful. We a priori believe that it cannot, because, I repeat, dry air does not conform to hydrostatic equilibrium and its distribution will not inform us about the effect of gravity that we want to subtract from condensation-induced density changes. And indeed, it appears that using S_d ≡ N_v/N_d ∂N_d/∂z as a reference produces a non-sensical physical result (although mathematically it’s ok). In this case we would have, instead of (34), that S = ∂N_v/∂z – N_v/N_d ∂N_d/∂z ≡ S_d.

But it is easy to see that Eqs. (32)-(33) (at ∂N_v/∂x =0)can be re-written as
u∂N/∂x = (S – S_d)/&gamma_d (here S is an unknown function)
So if we put S = S_d (having dry air as reference) we obtain that
u∂N/∂x = 0. In other words, winds cannot blow parallel to air pressure gradient. This result is clearly invalid.

So, this is our physical argumentation for S (34). I hope people can see that there ARE physically independent arguments. I.e. (34) was formulated without any reference to the continuity equation, only considering (1) the vertical direction of temperature gradient, (2) condensation caused by motion, and (3) gravitational expansion in hydrostatic equilibrium. But, additionally, there is an absolutely independent way of deriving (34). When the physics is right, you can come to the same conclusion from different sides. I will dwell on this independent derivation separately.

Anastassia,
You say that 34 is based on independent physics. But if so, it must have numbers associated with that physics. If the formula depends on gravity, where is g? If thermal, where are the specific heats? Or temperatures?

You say that “S must be proportional to the velocity component that is parallel to temperature gradient.” but there is nothing quantitative about what the temperature gradient is. Yet the proportionality is precise:
S = w∂N_v/∂z
All you’ve done is said that the velocity can be assumed vertical. You may say that it’s because of the layered temperature field, but that is not part of the basis of the equation. It cauld be 1D flow for any of several reasons – same equation. What it does say is that a parcel of constant volume can only change its density over a distance if it sheds mass at rate S. That is what determines the constant of proportionality – not the temperature gradient or the amount of graviry.

In math terms, if you have an increment Δz and constant w, then the nett wv flux per unit area is wΔN_v, and since water must be conserved, the volume precipitation must be S Δz. That is what gives you your first equation.

Then you correctly observe that w might not be constant. The air might be converging or diverging. So then,
S Δz = ΔwN_v = wΔN_v + N_vΔw
An extra term. How to find it? As you do, by tracking a reference gas that flows with the wv but does not change its mass.

This cannot be the air N (Nd+Nv). That is losing water. It must be the dry component N_d. The coresponding expression for it is
0 = wΔN_d + N_dΔw.

Anastassia,“How do you justify it?”
Easily. Physics is quantitative. You always need to know, how much?
If 34 depends on gravity, then what gravity. If g does not appear, then is it in Earth? Mars? The Moon? The formula is the same in all cases. Therefore it does not depend on gravity.

Easily. Physics is quantitative. You always need to know, how much? If 34 depends on gravity, then what gravity. If g does not appear, then is it in Earth? Mars? The Moon? The formula is the same in all cases. Therefore it does not depend on gravity.

Nick, I am utterly surprised. What about parametric dependencies? They do not exist? So if there is gravity, it must explicitly show up as g? And if a formula does not contain g, it may not depend on gravity?

As I said above, total air rather than dry air is used because we assume a priori that total air conforms to hydrostatic equilibrium. Therefore, changes in density N of total air are governed by hydrostatic equilibrium condition dp/dz = -ρ g = -NM g. Using the hydrostatic equilibrium and the ideal gas law you can easily express the reference term γ ∂N/∂z via g and temperature. If you have difficulties, I’ll show you the answer.

Is your statement that
“The formula is the same in all cases. Therefore it does not depend on gravity.”
your only argument against our physical arguments for Eq. (34) or you have others?

Other physical laws do exist, but you have not used them. You have taken the continuity equation once more, this time in an approximate form. Then you have required that the exact law and the approximate law are simultaneously in force and exactly. From that spurious requirement you get totally erroneous results.

“As I said above, total air rather than dry air is used because we assume a priori that total air conforms to hydrostatic equilibrium.”

I can see no relevance in that. You don’t need to use either pressure or gravity to get the missing term, which is velocity gradient. But the point is that total air isn’t non-condensable. In fact, it gains or loses exactly as much mass as the vapor component, ie S.

The equation (34) is not an equation that tells what the source term is. It’s just the continuity equation, only a wrong continuity equation. There’s absolutely nothing else in that equation from any physical principles.

So if you had S=S_d, you would have u ∂N/∂x =0. But you also has this equal to S. So S=0? It never rains but it pours from dry air?

Eq. (A7) is nothing but a combination of (32)-(33) and ∂N_v/∂x = 0. So, Eq. (A7) does not in any way depend on (34).
It is u∂N/∂x = (S-S_d)/γ_d.

Here, S_d is nothing but a definition: S_d = ∂N_v/∂z – γ_d ∂N_d/∂z, while S is as unknown as it remained in (32)-(33).

So, if you put S = S_d, with this additional equation you obtain u∂N/∂x = 0, which is, as I said above, non-sense in the general case.

But if you additionally involve Eq. (34), you obtain S = 0.

Note that this result, S = 0, is a product of five equations for five variables that I clarified above: (32)-(33), ∂N_v/∂x = 0, (34), AND your own equation S = S_d, which is equivalent to ∂N/∂x = 0. So mathematically it is fine, and you are again concerned about physics. What would this mean? I’ll tell you.

Anastassia,“Nick, I cannot see why you continue to interpret C as a kinetic constant, which we never did,”
Well, you said in part A1:“The linearity assumption is justified by the particular physical nature and stoichiometry of condensation, with gas turning to liquid: condensation is a first-order reaction over saturated molar density Nv of the condensing gas. This can be experimentally tested by considering condensation of water with different isotopic composition (e.g., Fluckiger and Rossi, 2003).”

And indeed, F&R is a place where you’ll find a discussion of molecular kinetics.

On C, you said:“In chemical kinetics C depends on temperature and the molecular properties of the reagent as follows from the law of mass action. Since the saturated concentration N_v of condensable gas depends on temperature as dictated by the Clausius-Clapeyron law, we can ask what the proportionality coefficient C physically means in this case. Different substances have different partial pressures of saturated vapor at any given temperature – this is controlled by the vaporization constant L and the molecular properties of the substance. Note too that for any given substance (like water) the saturated concentration depends on various additional parameters including the curvature of the the liquid surface and availability of condensation nuclei.”

No mention there of ” the vertical velocity and the degree of deviation of water vapor pressure from hydrostatic equilibrium”.

But the main thing is, if your justification for S=CN_v isn’t first order molecular kinetics, then what is it? It can’t be everyday observation.

Before addressing Nick’s points about S = 0 and rain from dry air, which are very worth addressing, I will now show how S (34) can be derived in a different way than wha we described in our paper as above.

This complementary physical picture is presented in the blog. We start from the proposition that the potential energy associated with the non-equilibrium vertical pressure gradient of water vapor is what drives the circulation. As I explained above, in a 1-D case when there is only saturated water vapor and a temperature gradient, this potential energy is very visible and drives significant air motions. We propose that in 3-D case this potential energy — if condensation is present — does not mysteriously disappear, but continues to drive the gas motion. Nobody has ever looked at this process before, this is indeed a new and testable proposition.

This potential energy released per unit time proportionally to vertical velocity determines the atmospheric circulation power q (the motor) as per Eq. (3) in the post, where the opposing effect of gravity is accounted for. Next, we assume as before that the atmosphere is in hydrostatic equilibrium. This means that kinetic energy is generated by horizontal pressure gradients only (with vertical pressure gradients balanced by gravity). Equating q to u∇p as per Eq. (4) immediately yields Eq. (37) in the paper (which is our main result). As one can see, no continuity equation has been involved.

Note that these energy considerations do not involve any mysterious small factor that is causing confusions, but unambiguously determine the circulation power as q = wp_v (1/hv – 1/h).

Now then combining it with (32)-(33) for a horizontally isothermal atmosphere we naturally obtain S (34). So S (34), originally formulated from different considerations (although again involving hydrostatic equilibrium), is consistent with independent energy considerations. This overall consistency is also described in the paper, e.g. the condensation-related force f_c as formulated on p. 1044 is equal to f_c = S RT/w.

(Note that if the atmosphere is not horizontally isothermal, S (34) will not follow from (37) (or Eq. (4) in the post). But in this case q (3) will also be diferent, because the non-equilibrium water vapor pressure gradient will not be vertical. But this is a separate story beyond the horizontally isothermal case considered in the paper.)

The few concrete points I have brought up are not just irrelevant nitpicking. They seem to be at the heart of your paper. There’s almost nothing left when they are taken into account.

You have accepted, in a way, one of the criticism claiming that it’s not really relevant as the whole chapter is just additional comments. Strong claims have, however, been presented in your paper based on that erroneous part.

This is probably more essential for the rest, because here you take advantage from the fact that from one contradiction it’s possible to draw anything. Forcing a non-zero to zero has such a power.

Joshua,
Yes, if you have followed the main author as long as I have you would know that she will never engage willard on his direct question.

Steven, willard never asked me any questions. Nick did, even you did even if refused to clarify what you meant, and I am doing my best to answer. But to do you a pleasure if you will formulate what the direct question of willard is, I will respond (of course, if I know the answer and if the question is pertinent to science).

If you read my comments as you say you did, you should know that no one answered it yet. I have a feeling you know why I’m asking this: it is related to Eli’s comment a bit earlier, to which you commented yourself and against which Douglas has nothing more than diverting away with an equivocation on the word “flaw”.

For the sake of openness, I can tell you why I’m asking this question: I want to know to which extent editors courteously trampled on the reviewers’ public comments and gave you a free pass.

***

If the editors decided to disregard the reviewers’ comment and publish the paper (we can help Douglas and invoke Feyerabend’s “anything goes” here) my question remains to be answered by the authors and the reviewers.

I’m not asking you to respond for Judy, who might be too busy to respond to a question that might be lacking in substance, if we’re to believe Douglas’ judgement on substantiveness. Considering his glosses on falsifiability, others might consider that this question deserves to be answered.

***

As you can see, I can be quite forthright. Since I’m not sure my interlocutors want everyone to notice how the limits of their justified disingenuousness is being underlined, I try to remain cryptical. But when they ask for it, I will do the best I can to say what I mean in the clearest way I can.

Sorry to include some jabs at Douglas, but quite frankly, he would deserve worse than that. Since you’ve read Steve’s, I’m sure you know what I mean. His uninspired excuses are doing you a disservice. I don’t know why he would think that his tricks would escape philosophically-minded people, a cast who is basically paid to read mischievous arguments.

willard, thank you for your question. Our reply to Judy’s review is public, so you can read and decide for yourself.
The review has four points. Point one is addressed in our reply to Nick Stokes posted 26 January 2011. An appendix was included into the revised text with additional considerations on Eq. 34. We did not change the notations, because the physics of our approach, that is related to the ideal gas law, is best illustrated based on molar densities rather than mass densities. We generally believe that the standard notations that introduce a gas-specific constant to the ideal gas law are misleading. They are obscuring the fundamental nature of the universal gas constant.
Point two suggested an alternative between “This needs to be demonstrated either in the context of a more comprehensive scale analysis that includes the Navier Stokes equations” and “numerical model simulations using mesoscale or weather or climate models.”, the purpose of which to clarify the degree to which the effect “matters”. While the paper has been under review, two of us made two detailed accounts of condensation-induced dynamics on two drastically different spatial scales — hurricanes and tornadoes. Note that in these two papers we not only derived wind velocities, but also theoretically determined turbulent friction coefficient — something in principle unachievable in conventional simulations (where this coefficient is parameterized). The results of these papers were included into the revised text and discussed in a broader context of the other findings.
Additionally, we indicated that there is a different way of responding to the reviewer’s concern of estimating how the effect matters. A new section and a new figure (Fig. 2) was introduced comparing an effect that is known to matter (CAPE) and our effect. This is section 3.4 in the revised text.
Point three — we introduced a more extensive discussion of the ideas surrounding Hadley cell as indicated in our reply to JC.
Point four — in our response we presented a literature-based discussion defending our statement in the paper concerning the surface-specific nature of evaporation. Since the reviewer indicated that it anyway unlikely impacts our conclusions, this discussion was not included into the revised text.

Please if you have any specific questions, I’ll be happy to respond as time permits. I’ve basically done my program here — Nick has just got the idea how to (in)validate our propositions empirically, so the others will be able to do so as well. That will inspire critical and constructive thinking about our work. That has been our major goal.

Regarding Steven McIntyre’s blog, indeed it is where I learnt the blog culture (it was the first blog in my life where I commented) and I am grateful to people there from whom I learnt a great deal.

Please note that all the statements of Douglas concerning our paper represent a co-ordinated position of all the authors, including myself. If there are any particular things that especially concern you, we can discuss them and clarify misunderstandings.

On a personal note, some of your more philosophical statements are really interesting and it would be interesting to discuss them in greater detail. But as I said earlier today I do not feel your language well enough to chat in a more relaxed way. E.g. Max thinks you are preparing a legal case against us. But anyway thanks for your interest.

max,
Spend some time reading more of willard. read some of the source material he refers to. One minute he might appear marginal and cryptic, but after a while you can see what he sees. Resist the urge to say it makes no sense. For a long while I felt that way. Then I looked at it like a puzzle. That helped. Then I thought.. Tobis likes him. Tobis is no dummy ( although we disagree ) maybe I should push harder on Mosh to understand willard. In the end, that extra effort is worth it. And no that does not mean I agree with everything he says. But rather, that what he has to say is worth the effort to think first, read more completely and ask clarifying questions before going off half cocked. Put another way,
I always check the comments links to see if he has commented. Always a good bet. Not a sure thing, but a good bet.

Anastassia, I posted something yesterday under Nick’s comment about Sec 4.1 showing that your claim that condensation and a horizontal pressure gradient sustain each other can be proven exactly from the thermodynamics in Section 2.1: (also in your mail)

If you replace in your (33) N_v by N_v/N_d, u by N_d*u and v by Nd*v, you get: ∇(N_v/N_d) . (u,v)= S/N_d, which has characteristics
dx/dt= u,
dz/dt= w,
d(N_v/N_d)/dt= S/N_d,

with N_v/N_d= γ/(1-γ)
Now I tend to agree with you about the nature of the “source” term: it should not be seen as an independent physical source term, but simply expresses what should happen according to the relationships in Section 2.1. That means that along the characteristic,
d(N_v/N_d)/dt= w ∂(N_v/N_d)/∂z,
so
S= w N_d ∂(N_v/N_d)/∂z = w N (1-γ) ∂(γ/(1-γ))/∂z

and so you also have your compensation for overall volume expansion right there.

I think that is it, nothing new or unphysical. So you are right, your equations in 4.1 are pretty close anyway, but the one above is rigorously derived.That saves a long Appendix :).

Your claim proven as a theorem now means basically (with some radiative cooling at the top for the return flow) that it does not need confirmation by numerical modelling, but rather, application, to see how it plays out in real atmospheric problems.

The paper studies certain previously extensively studied processes of the atmosphere taking little advantage from the earlier literature. They start from the correct fundamental equations of physics but without specifying initially the overall physical setup. The first part of the derivations are done correctly but a few strange sentences are included, and one of them is used as a strawman argument against criticism of Held.

Next they make an artificial comparison that’s totally irrelevant, but used erroneously to justify the importance of the effects they study.

Then they write three equations, the third of which should be derivable from the previous two, but that one is written erroneously and is therefore in contradiction with the previous two. This contradiction from the error of the third equation is used to derive results that are essential for the continuation.

(There’s one thing that I’m personally happy. Before going trough the paper in any care I made intuitive conclusions on what kind of errors the paper must have. Those inclusive conclusions are now proven to be correct. It’s nice to get confirmation that my intuition still works.)

This excerpt from my earlier comment tells perhaps best about my reasoning and role of intuition in that:

How they reach such conclusions from the changes described above is another question. My view is that they don’t give sufficient emphasis on discussing the physics but perform calculations that are not really applicable for the physical case. Such calculation may get spurious strong results by applying some unphysical constraints, which exclude natural processes that occur in vertical direction and are therefore forced to introduce excessively strong effects horizontally. It’s possible that they use altitude as vertical coordinate in a situation where geopotential height would be more appropriate. I have not tried to figure out, whether this is the reason.

Based on more traditional ways of looking at the same physical situation I was virtually certain that their results were seriously wrong. That made me to speculate on the possible nature of the error in the paper. The most likely explanation was a erroneous assumption on the role of “horizontal” and use of that to get a spurious constraint equation.

That’s exactly what the set of equations (32), (33), and (34) does. There’s an extra constraint related to handling horizontal differences versus vertical ones that’s created by using simultaneously all three equations. That’s just of the nature I speculated about in the excerpt.

Nick Stokes | February 4, 2013 at 12:10 am |
“Nick, “nutty results” and “mathematical contradiction” is not the same”

Anastassia,
Well, if that semantics is important to you, let’s deal with the nutty results.

No, Nick, the difference between mathematics and physics is not semantic. Mathematical coherence is necessary (but insufficient) for a theory to be valid. If there is a mathematical contradiction, i.e., say your system of equations yields x = 0 AND x = 1 at the same time, there is nowhere to go from here. As I already said above, publishing such a paper would have been of course a bad editorial mistake.

If, on the other hand, the system of equations is mathematically coherent, and unambiguously yields x = 0, then you can make the next step and try to verify your theoretical result by empirical evidence, i.e. to see if x is indeed zero.

I just want to emphasize once again that the system (32)-(34) is mathematically coherent. Your claims about the system being overdetermined or there being any mathematical contradiction are unsubstantiated.

No, 34 is just a version of 32/33 with some terms (horizontal components) omitted, with the argument that they can be neglected against the main terms. There’s a mistake, but i’s a distraction to dwell on that. I’m not sure if dropping those terms is justified, but this is commonly done in continuum analysis (when justified). What is never done is put the original equation together with its simplified derivative into the same set of equations.

The dropped terms were dropped because they were small relative to the main terms, not because they are known to be absolutely zero. There is no justification for such a belief, but keeping both equations asserts it, because the equation and its simplifier can be subtracted. And in your case, that becomes explicit with equation A7. And the results following Eq 36 reflect that.

Try to follow my comment Nick (Feb 4 2:28 above) and you see that something almost equal to Anastassia’s result follows exactly as a consequence of mass balance and the assumption of saturation (which fixes the vertical gradient of N_v/N_d). So her result is correct to a very good approximation and is easily made exact. You just can’t avoid this result.

Cees,
Yes, your formula is exactly the same as the ,a href=”http://judithcurry.com/2013/01/31/condensation-driven-winds-an-update-new-version/#comment-291818″>one I derived. It is a consequence of conservation of mass, and could have been derived directly from 32 and 33 by dropping horizontal components.

The issue is, having simplified 32/33 to 34, you can’t use both. In fluids, if viscosity is unimportant, you can solve with the Euler equations rather than Navier-Stokes, dropping the viscous stress term. But you can’t use both.

SM 1.14pm Carnap and cars? Don’t drive a Volvo meself, prefer a
souped up Ford. Re my comment, SM, I didn’t say that for for
‘something (a process,situation?) to be true it has to be empirically falsifiable,’ What i said was that for a ‘statement to be true it has to correspond to reality and this means being subject to a process of
verification /falsification. Hmm, verification?
As there’s a serious discussion going on here I’ll have a go at
responding re logical positivism in me simple fashion anon on
‘Open Thread.’ Sm. Bc

your last reply refers to a lengthy physical explanation of what the source term should be. That is all fine, but if you follow my derivation, you see that your explanation only gives an approximate expression, whereas the one I gave is very simple (just the geometry of the hyperbolic equation), and gives an exact result and not an approximation; the change in time of N_v/N_d along the characteristic CAN BE NOTHING ELSE then w times the vertical gradient in N_v/N_d: the latter is already fixed because of saturation, so it is there already and you just read it off along the characteristic. This argument supersedes all other considerations you have come up with. So it is really very simple.

and I am not saying this to suggest that there is anything trivial about your results: on the contrary, I think it is profound and original and may have a big impact on a lot of issues in weather and climate; having looked at it in a little more depth only makes it better. So thank you for posting and discussing it here.

The paper makes an explicit error in the derivation of formulas (36) and (37) when it requires that the exact continuity equation and the approximate continuity equation are simultaneously valid. That requirement leads here to results that are fully spurious.

There’s nothing of interest left, when the erroneous derivation is removed.

I just want to go over some basics as I see them.
H20 gas condenses on some kind of surface- H2O gas doesn’t just condense with other H2O gas. Though H2O gas condenses on liquid
H2O.
All gases of gas mixture can be regarded to have a partial pressure
or vapor pressure. So what control evaporation of water is existing
vapor pressure of the air in contact with the liquid water and the temperature of the air. Wiki:
“The vapor pressure that a single component in a mixture contributes to the total pressure in the system is called partial pressure. For example, air at sea level, and saturated with water vapor at 20 °C, has partial pressures of about 23 mbar of water, 780 mbar of nitrogen, 210 mbar of oxygen and 9 mbar of argon.”
So if pressure is constant it, the partial pressure of H2O could increase, but also temperature in constant, a increase in pressure also corresponds
increase in partial pressure [or decrease in pressure, decreases H20 partial pressure.

Or if had atmosphere of pure H2O gas, 1 atm of pressure requires temperature of 100 C- or if the gas was cooler 100 C, H20 gas does condense with other H20 gas molecules. And lower pressure say 1/2 atm pure gas H20 gas would condense at lower temperature.
H2O at above -150 C will evaporate into a vacuum or in atmosphere which has zero partial pressure of H20 gas.
The water phase diagram:

At somewhere around 23 mbar if you had atmosphere of pure H20 gas and
it’s at 20 C, then H2O gas could condense with other H20 gas. But in gas mixture it doesn’t- it need a some liquid or solid to condense to.
Or at least that the way I understand it.
Though these gas molecules “try” to stick together, but the energy of all the other types of gases disrupt this from happening. Or H2O gas is not ideal gas because instead bouncing around freely it’s sticking to other H2O molecules and being forced apart by other molecules of gas.
But if somehow enough H20 gas molecules become a liquid droplet of water there some critical amount of molecules- as wild guess, say 1000 molecules formed as liquid water- in which H20 gas can more than just briefly condense onto such a droplet of water.
So if water molecule formed with say 5 molecules of H2O liquid droplet, within some period measured in nanoseconds, and if this other gas molecule condensed making 6 molecules, than they may fly apart within nanoseconds or less than a second. But if one molecule of gas join with droplet of 1000 or more molecules of water then it might not evaporate for many seconds- a water molecule and many water molecules may stay as water molecule for a long period time.
Or if the there enough water molecule in droplet the water acts similar to a drop water from dripping facet or pool of water- which a portion of it is evaporating and condensing- but with H20 gas molecules in a gas mixture most of gas molecules are transiting from gas to liquid state within a time frame of something like less than a second.

So start with water surface. 1 mm above the surface there is H20 gas.
Some Water molecules from liquid are becoming a gas and lasting in this gas phase lasting for less an 1 second before returning to the liquid, some portion of this H20 gas gets beyond 1 mm, they may go to 1 cm, or 1 meter or 1 km [etc] high without returning to the liquid water surface, and have zillions of transitions from gas to liquid state, before become a rain drop and falling into the ocean.
And so water droplets starting with 2 molecules of H20 to billions of molecules of H2O.
A Rain drop 3 mm diameter: “4.716278×10^20 molecules”:

Now, a rain drop remain buoyant until it reaches a certain size, and cloud with updrafts can have larger raindrops kept buoyant and rain rain may increase it’s size falling.
Now a raindrops without updrafts which comprised of “4.716278×10^20 molecules” is going to fall, but smaller droplets are going float without
updrafts. Fog is can be not fall much in quite still air and it’s small droplets of water- 1/1000th to 10th mm diameter range.
And 1/1000th mm is about 1.0 x 10^10 molecules.
So roughly if less than 1 trillion molecules it will be buoyant in air.
And somewhere less the 1 million molecules they will not be very visible or noticeable.
And these smaller droplet aren’t going last very long- they will have very fast evaporation rate in dry enough air.
So lots of them near ocean surface. If live near an ocean you get salt corroding everything- so have these water droplet- not formed from condensation [that would be pure water and not a problem] but wind and waves mechanically making these droplets, plus high humidity of general environment preventing them from evaporating quickly.

Now read stuff about this salt from ocean is suppose to have something to do with cloud formation, but my experience is you have to be fairl close to ocean to have this corrosion issue and and can’t imagine much salt getting above 1000 meter in elevation.

And trying over how water vapor condenses, but this getting long, so
anyone got any answers, that would be good.

You are right in that water does not condense in pure air immediately the saturation point is exceeded. Some supersaturation is needed before droplets start to be formed. When the relative humidity exceeds by more than 10% the saturation level the condensation proceeds rapidly under ideal conditions. In less ideal conditions that occurs earlier.

In ascending convection of the real atmosphere the supersaturation may be as high as a few percent, but rarely more. That’s largely due to the presence of aerosol impurities.

Nick, I see, so we agree what it should be. Nevertheless, I the whole point of Anastassia was to demonstrate that in a 2D motion, saturation is proportional to a horizontal pressure gradient times a factor relating horizontal and vertical scales of velocity. I think this point is indisputable. And her approximation is rather accurate anyway. So we are really talking about finer details. It should not be the case that these prevent publication of an overall very good and original paper with potentially a high impact.

“And her approximation is rather accurate anyway.”
Let me go back to my earlier analogy. Start with an equation that says
x=0.9999. So far so good. Then make some simplifications. You get x=1. That is rather accurate anyway.

So put them in your equation mix. We can subtract: 0=.0001. Well, OK. Then multiply by 10000 – you can always do that. So 1=0. Getting a bit nihilist…

That’s what happens when you solve an exact expression together with a rather accurate approximation.

Cees, thank you very much for your support. But I am sorry to disappoint you — if you use your equation instead of Eq. (34) and solve it together with (32)-(33) and ∂N_v/∂x = 0, you will get a physically meaningless result:
u∂N/∂x = 0.
Mathematically it is fine. But it means that over an isothermal surface the winds never blow along the pressure gradients. This is certainly not true, as in hurricanes for example radial convergence is responsible for all precipitation. This shows that your equation and Nick’s, and the logic behind your derivation, is physically incorrect — irrespective of whether Eq. (34) is correct or not.
Your mistake (as well as Nick’s) is that you disregard the importance of hydrostatic equilibrium in determining the change of total air density and believe that Eq. (34) is somehow related to (32)-(33). It is not. It does look similar, but there is a profound difference.
Note also that here there is an independent derivation of (34).

” if you use your equation instead of Eq. (34) and solve it together with (32)-(33) and ∂N_v/∂x = 0, you will get a physically meaningless result:”
Indeed you do. It isn’t independent. And adding in a simple error doesn’t make it more meaningful.

You continue to attempt making something from nothing. You make unjustified assumptions and derive spurious results from them.

Separating vertical and horizontal cannot be done like that. You must present full equations without unjustified assumptions that any particular variable does not depend on x to get correct equations. Your results are spurious consequences of failure to do that.

You are also totally wrong in claiming “Nobody has ever looked at this process before, this is indeed a new and testable proposition.” as that has been done more correctly in every standard derivation of moist lapse rate. There are approximations in those, but not errors like in yours.

So put them in your equation mix. We can subtract: 0=.0001. Well, OK. Then multiply by 10000 – you can always do that. So 1=0. Getting a bit nihilist…

Nick, what you are talking about is a mathematical contradiction. As I repeatedly said in this thread, the system (32)-(34) is coherent. You cannot derive anything like 1=0 from it. So this claim that you are perpetuating is incorrect. I said it several times, but you were changing topic — see here, here and here — instead of conceding this obvious point.

If you are able to produce anything like 1=0 from (32)-(34), please do. I am sure that people will appreciate it. If you cannot, why to repeat this unsubstantiated claim?

Anastassia,
Cees and I have independently derived the correct form from Eqs 32/33. Pekka agrees. Isaac Held derived the same form (Eq 1). It’s elementary. Yet you insist that we’re all wrong and your very similar form is the only one that is right, because it uses different physics. Yet you cannot point to any quantitative contribution that that physics makes. Your explanations are arm-waving.

Nick, you have changed the topic once again and have not replied to the mathematical contradiction issue.

I not merely insist that you are wrong, I give a very clear reason — your derivation is wrong, because it produces a physically meaningless result,
namely -u∂N/∂x = 0. So, whatever you think of my derivation, yours is incorrect. (Dr. Held referred to your comment on this issue, by the way.)

Ok, you say that my explanations are arm-waving. But you did not show any error in these explanations. You just said that it is wrong because it does not contain gravity. And added that you see “no relevance” in our derivation. That sums up your critique so far. But to “see no relevance” and show an error are different things.

Your own derivation of S is incorrect, as shown by the result its produces, u∂N/∂x=0. You see, it is not just “no relevance” or accusation of “arm-waving” from my side, it is simply a statement that contradicts the evidence. Our Equation (34) produces a result that makes a lot of sense;
-u∂N/∂x = S.
It is also empirically testable — and has been tested and gave meaningful results. Besides, it is derived independently from two independent set of physical considerations here and here.
If you continue to ignore this evidence, there is little difference from arm-waving.

There are, indeed, fully obvious explanations for reaching the equation (34) as an approximation. I cannot imagine any connection with an equation of that form to anything else than the continuity equation. You have not given any plausible derivation for that equation from physics beyond the continuity.

That’s one point, but there’s also the second point that you must justify fully every claim that some partial derivative over x is zero. You have not given proper justification for the assumption that N_v does not depend on x. That would be the case if nothing else would depend on x either, but then pressure would also be independent of x. Now you assume that the partial pressure of dry air component does depend on x but that of vapor does not. That could be explained if the temperature would not depend on x, but having a different overall pressure means that you lose all justification for that assumption as lower pressure means more adiabatic expansion and that means a lower temperature.

Anastassia,
If you want a contradiction, here it is. In the notation of A7, our form is S=S_d. Your A7 is S-S_d=γ_d w ∂N_v/∂x. Now in deriving 34, you set horizontal derivatives to zero, including N_v. So S=S_d. We’re right! That’s a contradiction, isn’t it?

You say we’re wrong, despite not being able to say where (three independent derivations). You say so because it leads to a ridiculous result. I wearily point out that that is exactly what Pekka and I have been saying. Using 34 with 32/33 willlead to ridiculous results. That’s the point of my x=0.9999 analogy. x=0.9999 isn’t wrong. x=1 isn’t wrong. But together they lead to a ridiculous result..

You just add in an obvious error to get more complicated ridiculous results.